diff --git a/CODE_GUIDELINES.md b/CODE_GUIDELINES.md
index 439eee8..3e2bbd0 100644
--- a/CODE_GUIDELINES.md
+++ b/CODE_GUIDELINES.md
@@ -2849,12 +2849,14 @@ Building accessible applications ensures that all users, including those with di
 
 **Required Fields:**
 
+Which member fields are required (asterisk, tooltip, validation) is configured in **Settings** (Memberdata section: edit a member field and set "Required"). The member create/edit form and Member resource validation both read `settings.member_field_required`. Email is always required; other fields default to optional.
+
 ```heex
-<!-- Mark required fields -->
+<!-- Mark required fields (value from settings or always true for email) -->
 <.input
   field={@form[:first_name]}
   label={gettext("First Name")}
-  required
+  required={@member_field_required_map[:first_name]}
   aria-required="true"
 />
 ```
diff --git a/lib/membership/member.ex b/lib/membership/member.ex
index 7b70e89..3af514e 100644
--- a/lib/membership/member.ex
+++ b/lib/membership/member.ex
@@ -500,48 +500,97 @@ defmodule Mv.Membership.Member do
       end
     end
 
-    # Validate required custom fields (actor from validation context only; no fallback)
+    # Validate required custom fields (actor from validation context only; no fallback).
+    # Only for create_member/update_member; skip for set_vereinfacht_contact_id (internal sync
+    # only sets vereinfacht_contact_id; custom fields were already validated and saved).
     validate fn changeset, context ->
-      provided_values = provided_custom_field_values(changeset)
-      actor = context.actor
+               provided_values = provided_custom_field_values(changeset)
+               actor = context.actor
 
-      case Mv.Membership.list_required_custom_fields(actor: actor) do
-        {:ok, required_custom_fields} ->
-          missing_fields = missing_required_fields(required_custom_fields, provided_values)
+               case Mv.Membership.list_required_custom_fields(actor: actor) do
+                 {:ok, required_custom_fields} ->
+                   missing_fields =
+                     missing_required_fields(required_custom_fields, provided_values)
 
-          if Enum.empty?(missing_fields) do
-            :ok
-          else
-            build_custom_field_validation_error(missing_fields)
-          end
+                   if Enum.empty?(missing_fields) do
+                     :ok
+                   else
+                     build_custom_field_validation_error(missing_fields)
+                   end
 
-        {:error, %Ash.Error.Forbidden{}} ->
-          Logger.warning(
-            "Required custom fields validation: actor not authorized to read CustomField"
-          )
+                 {:error, %Ash.Error.Forbidden{}} ->
+                   Logger.warning(
+                     "Required custom fields validation: actor not authorized to read CustomField"
+                   )
 
-          {:error,
-           field: :custom_field_values,
-           message:
-             "You are not authorized to perform this action. Please sign in again or contact support."}
+                   {:error,
+                    field: :custom_field_values,
+                    message:
+                      "You are not authorized to perform this action. Please sign in again or contact support."}
 
-        {:error, :missing_actor} ->
-          Logger.warning("Required custom fields validation: no actor in context")
+                 {:error, :missing_actor} ->
+                   Logger.warning("Required custom fields validation: no actor in context")
 
-          {:error,
-           field: :custom_field_values,
-           message:
-             "You are not authorized to perform this action. Please sign in again or contact support."}
+                   {:error,
+                    field: :custom_field_values,
+                    message:
+                      "You are not authorized to perform this action. Please sign in again or contact support."}
 
-        {:error, error} ->
-          Logger.error(
-            "Failed to load custom fields for validation: #{inspect(error)}. Required field validation cannot be performed."
-          )
+                 {:error, error} ->
+                   Logger.error(
+                     "Failed to load custom fields for validation: #{inspect(error)}. Required field validation cannot be performed."
+                   )
 
-          {:error,
-           field: :custom_field_values,
-           message:
-             "Unable to validate required custom fields. Please try again or contact support."}
+                   {:error,
+                    field: :custom_field_values,
+                    message:
+                      "Unable to validate required custom fields. Please try again or contact support."}
+               end
+             end,
+             where: [action_is([:create_member, :update_member])]
+
+    # Validate member fields that are marked as required in settings or by Vereinfacht.
+    # When settings cannot be loaded, we still enforce email + Vereinfacht-required fields.
+    validate fn changeset, _context ->
+      vereinfacht_required? = Mv.Config.vereinfacht_configured?()
+
+      required_fields =
+        case Mv.Membership.get_settings() do
+          {:ok, settings} ->
+            required_config = settings.member_field_required || %{}
+            normalized = VisibilityConfig.normalize(required_config)
+
+            Enum.filter(Mv.Constants.member_fields(), fn field ->
+              field == :email ||
+                (vereinfacht_required? && Mv.Constants.vereinfacht_required_field?(field)) ||
+                Map.get(normalized, field, false)
+            end)
+
+          {:error, reason} ->
+            Logger.warning(
+              "Member required-fields validation: could not load settings (#{inspect(reason)}). " <>
+                "Enforcing only email and Vereinfacht-required fields."
+            )
+
+            Enum.filter(Mv.Constants.member_fields(), fn field ->
+              field == :email ||
+                (vereinfacht_required? && Mv.Constants.vereinfacht_required_field?(field))
+            end)
+        end
+
+      missing =
+        Enum.filter(required_fields, fn field ->
+          value = Ash.Changeset.get_attribute(changeset, field)
+          not member_field_value_present?(field, value)
+        end)
+
+      if Enum.empty?(missing) do
+        :ok
+      else
+        field = hd(missing)
+
+        {:error,
+         field: field, message: Gettext.dgettext(MvWeb.Gettext, "default", "can't be blank")}
       end
     end
   end
@@ -1420,4 +1469,14 @@ defmodule Mv.Membership.Member do
   defp value_present?(_value, :email), do: false
 
   defp value_present?(_value, _type), do: false
+
+  # Used by member-field-required validation (settings-driven required fields)
+  defp member_field_value_present?(_field, nil), do: false
+
+  defp member_field_value_present?(_, value) when is_binary(value),
+    do: String.trim(value) != ""
+
+  defp member_field_value_present?(_, %Date{}), do: true
+  defp member_field_value_present?(_, value) when is_struct(value, Date), do: true
+  defp member_field_value_present?(_, _), do: false
 end
diff --git a/lib/membership/membership.ex b/lib/membership/membership.ex
index 74735e4..2583718 100644
--- a/lib/membership/membership.ex
+++ b/lib/membership/membership.ex
@@ -64,6 +64,8 @@ defmodule Mv.Membership do
 
       define :update_single_member_field_visibility,
         action: :update_single_member_field_visibility
+
+      define :update_single_member_field, action: :update_single_member_field
     end
 
     resource Mv.Membership.Group do
@@ -257,6 +259,46 @@ defmodule Mv.Membership do
     |> Ash.update(domain: __MODULE__)
   end
 
+  @doc """
+  Atomically updates visibility and required for a single member field.
+
+  Updates both `member_field_visibility` and `member_field_required` in one
+  operation. Use this when saving from the member field settings form.
+
+  ## Parameters
+
+    - `settings` - The settings record to update
+    - `field` - The member field name as a string (e.g., "first_name", "street")
+    - `show_in_overview` - Boolean value indicating visibility in member overview
+    - `required` - Boolean value indicating whether the field is required in member forms
+
+  ## Returns
+
+    - `{:ok, updated_settings}` - Successfully updated settings
+    - `{:error, error}` - Validation or update error
+
+  ## Examples
+
+      iex> {:ok, settings} = Mv.Membership.get_settings()
+      iex> {:ok, updated} = Mv.Membership.update_single_member_field(settings, field: "first_name", show_in_overview: true, required: true)
+      iex> updated.member_field_required["first_name"]
+      true
+
+  """
+  def update_single_member_field(settings,
+        field: field,
+        show_in_overview: show_in_overview,
+        required: required
+      ) do
+    settings
+    |> Ash.Changeset.new()
+    |> Ash.Changeset.set_argument(:field, field)
+    |> Ash.Changeset.set_argument(:show_in_overview, show_in_overview)
+    |> Ash.Changeset.set_argument(:required, required)
+    |> Ash.Changeset.for_update(:update_single_member_field, %{})
+    |> Ash.update(domain: __MODULE__)
+  end
+
   @doc """
   Gets a group by its slug.
 
diff --git a/lib/membership/setting.ex b/lib/membership/setting.ex
index f56daa0..154288b 100644
--- a/lib/membership/setting.ex
+++ b/lib/membership/setting.ex
@@ -11,6 +11,8 @@ defmodule Mv.Membership.Setting do
   - `club_name` - The name of the association/club (required, cannot be empty)
   - `member_field_visibility` - JSONB map storing visibility configuration for member fields
     (e.g., `%{"street" => false, "house_number" => false}`). Fields not in the map default to `true`.
+  - `member_field_required` - JSONB map storing which member fields are required in forms
+    (e.g., `%{"first_name" => true, "last_name" => true}`). Email is always required; other fields default to optional.
   - `include_joining_cycle` - Whether to include the joining cycle in membership fee generation (default: true)
   - `default_membership_fee_type_id` - Default membership fee type for new members (optional)
 
@@ -42,6 +44,9 @@ defmodule Mv.Membership.Setting do
       # Update member field visibility
       {:ok, updated} = Mv.Membership.update_member_field_visibility(settings, %{"street" => false, "house_number" => false})
 
+      # Update visibility and required for a single member field (e.g. from settings UI)
+      {:ok, updated} = Mv.Membership.update_single_member_field(settings, field: "first_name", show_in_overview: true, required: true)
+
       # Update membership fee settings
       {:ok, updated} = Mv.Membership.update_settings(settings, %{include_joining_cycle: false})
   """
@@ -68,6 +73,7 @@ defmodule Mv.Membership.Setting do
       accept [
         :club_name,
         :member_field_visibility,
+        :member_field_required,
         :include_joining_cycle,
         :default_membership_fee_type_id,
         :vereinfacht_api_url,
@@ -84,6 +90,7 @@ defmodule Mv.Membership.Setting do
       accept [
         :club_name,
         :member_field_visibility,
+        :member_field_required,
         :include_joining_cycle,
         :default_membership_fee_type_id,
         :vereinfacht_api_url,
@@ -109,6 +116,17 @@ defmodule Mv.Membership.Setting do
       change Mv.Membership.Setting.Changes.UpdateSingleMemberFieldVisibility
     end
 
+    update :update_single_member_field do
+      description "Atomically updates visibility and required for a single member field"
+      require_atomic? false
+
+      argument :field, :string, allow_nil?: false
+      argument :show_in_overview, :boolean, allow_nil?: false
+      argument :required, :boolean, allow_nil?: false
+
+      change Mv.Membership.Setting.Changes.UpdateSingleMemberField
+    end
+
     update :update_membership_fee_settings do
       description "Updates the membership fee configuration"
       require_atomic? false
@@ -162,6 +180,44 @@ defmodule Mv.Membership.Setting do
              end,
              on: [:create, :update]
 
+    # Validate member_field_required map structure and content
+    validate fn changeset, _context ->
+               required_config = Ash.Changeset.get_attribute(changeset, :member_field_required)
+
+               if required_config && is_map(required_config) do
+                 invalid_values =
+                   Enum.filter(required_config, fn {_key, value} ->
+                     not is_boolean(value)
+                   end)
+
+                 valid_field_strings = Mv.Constants.member_fields() |> Enum.map(&Atom.to_string/1)
+
+                 invalid_keys =
+                   Enum.filter(required_config, fn {key, _value} ->
+                     key not in valid_field_strings
+                   end)
+                   |> Enum.map(fn {key, _value} -> key end)
+
+                 cond do
+                   not Enum.empty?(invalid_values) ->
+                     {:error,
+                      field: :member_field_required,
+                      message: "All values in member_field_required must be booleans"}
+
+                   not Enum.empty?(invalid_keys) ->
+                     {:error,
+                      field: :member_field_required,
+                      message: "Invalid member field keys: #{inspect(invalid_keys)}"}
+
+                   true ->
+                     :ok
+                 end
+               else
+                 :ok
+               end
+             end,
+             on: [:create, :update]
+
     # Validate default_membership_fee_type_id exists if set
     validate fn changeset, context ->
                fee_type_id =
@@ -219,6 +275,12 @@ defmodule Mv.Membership.Setting do
       description:
         "Configuration for member field visibility in overview (JSONB map). Keys are member field names (atoms), values are booleans."
 
+    attribute :member_field_required, :map,
+      allow_nil?: true,
+      public?: true,
+      description:
+        "Configuration for which member fields are required in forms (JSONB map). Keys are member field names (strings), values are booleans. Email is always required."
+
     # Membership fee settings
     attribute :include_joining_cycle, :boolean do
       allow_nil? false
diff --git a/lib/membership/setting/changes/update_single_member_field.ex b/lib/membership/setting/changes/update_single_member_field.ex
new file mode 100644
index 0000000..e24860c
--- /dev/null
+++ b/lib/membership/setting/changes/update_single_member_field.ex
@@ -0,0 +1,179 @@
+defmodule Mv.Membership.Setting.Changes.UpdateSingleMemberField do
+  @moduledoc """
+  Ash change that atomically updates visibility and required for a single member field.
+
+  Updates both `member_field_visibility` and `member_field_required` JSONB maps
+  in one SQL UPDATE to avoid lost updates when saving from the settings UI.
+
+  ## Arguments
+  - `field` - The member field name as a string (e.g., "street", "first_name")
+  - `show_in_overview` - Boolean value indicating visibility in member overview
+  - `required` - Boolean value indicating whether the field is required in member forms
+
+  ## Example
+      settings
+      |> Ash.Changeset.for_update(:update_single_member_field, %{},
+        arguments: %{field: "first_name", show_in_overview: true, required: true}
+      )
+      |> Ash.update(domain: Mv.Membership)
+  """
+  use Ash.Resource.Change
+
+  alias Ash.Error.Invalid
+  alias Ecto.Adapters.SQL
+  require Logger
+
+  def change(changeset, _opts, _context) do
+    with {:ok, field} <- get_and_validate_field(changeset),
+         {:ok, show_in_overview} <- get_and_validate_boolean(changeset, :show_in_overview),
+         {:ok, required} <- get_and_validate_boolean(changeset, :required) do
+      add_after_action(changeset, field, show_in_overview, required)
+    else
+      {:error, updated_changeset} -> updated_changeset
+    end
+  end
+
+  defp get_and_validate_field(changeset) do
+    case Ash.Changeset.get_argument(changeset, :field) do
+      nil ->
+        {:error,
+         add_error(changeset,
+           field: :field,
+           message: "field argument is required"
+         )}
+
+      field ->
+        valid_fields = Mv.Constants.member_fields() |> Enum.map(&Atom.to_string/1)
+
+        if field in valid_fields do
+          {:ok, field}
+        else
+          {:error,
+           add_error(
+             changeset,
+             field: :field,
+             message: "Invalid member field: #{field}"
+           )}
+        end
+    end
+  end
+
+  defp get_and_validate_boolean(changeset, :show_in_overview = arg_name) do
+    do_validate_boolean(changeset, arg_name, :show_in_overview)
+  end
+
+  defp get_and_validate_boolean(changeset, :required = arg_name) do
+    do_validate_boolean(changeset, arg_name, :member_field_required)
+  end
+
+  defp do_validate_boolean(changeset, arg_name, error_field) do
+    case Ash.Changeset.get_argument(changeset, arg_name) do
+      nil ->
+        {:error,
+         add_error(
+           changeset,
+           field: error_field,
+           message: "#{arg_name} argument is required"
+         )}
+
+      value when is_boolean(value) ->
+        {:ok, value}
+
+      _ ->
+        {:error,
+         add_error(
+           changeset,
+           field: error_field,
+           message: "#{arg_name} must be a boolean"
+         )}
+    end
+  end
+
+  defp add_error(changeset, opts) do
+    Ash.Changeset.add_error(changeset, opts)
+  end
+
+  defp add_after_action(changeset, field, show_in_overview, required) do
+    Ash.Changeset.after_action(changeset, fn _changeset, settings ->
+      # Update both JSONB columns in one statement
+      sql = """
+      UPDATE settings
+      SET
+        member_field_visibility = jsonb_set(
+          COALESCE(member_field_visibility, '{}'::jsonb),
+          ARRAY[$1::text],
+          to_jsonb($2::boolean),
+          true
+        ),
+        member_field_required = jsonb_set(
+          COALESCE(member_field_required, '{}'::jsonb),
+          ARRAY[$1::text],
+          to_jsonb($3::boolean),
+          true
+        ),
+        updated_at = (now() AT TIME ZONE 'utc')
+      WHERE id = $4
+      RETURNING member_field_visibility, member_field_required
+      """
+
+      uuid_binary = Ecto.UUID.dump!(settings.id)
+
+      case SQL.query(Mv.Repo, sql, [field, show_in_overview, required, uuid_binary]) do
+        {:ok, %{rows: [[updated_visibility, updated_required] | _]}} ->
+          vis = normalize_jsonb_result(updated_visibility)
+          req = normalize_jsonb_result(updated_required)
+
+          updated_settings = %{
+            settings
+            | member_field_visibility: vis,
+              member_field_required: req
+          }
+
+          {:ok, updated_settings}
+
+        {:ok, %{rows: []}} ->
+          {:error,
+           Invalid.exception(
+             field: :member_field_required,
+             message: "Settings not found"
+           )}
+
+        {:error, error} ->
+          Logger.error("Failed to atomically update member field settings: #{inspect(error)}")
+
+          {:error,
+           Invalid.exception(
+             field: :member_field_required,
+             message: "Failed to update member field settings"
+           )}
+      end
+    end)
+  end
+
+  defp normalize_jsonb_result(updated_jsonb) do
+    case updated_jsonb do
+      map when is_map(map) ->
+        Enum.reduce(map, %{}, fn
+          {k, v}, acc when is_atom(k) -> Map.put(acc, Atom.to_string(k), v)
+          {k, v}, acc -> Map.put(acc, k, v)
+        end)
+
+      binary when is_binary(binary) ->
+        case Jason.decode(binary) do
+          {:ok, decoded} when is_map(decoded) ->
+            decoded
+
+          {:ok, _} ->
+            %{}
+
+          {:error, reason} ->
+            Logger.warning("Failed to decode JSONB: #{inspect(reason)}")
+            %{}
+        end
+
+      _ ->
+        Logger.warning("Unexpected JSONB format: #{inspect(updated_jsonb)}")
+        %{}
+    end
+  end
+end
diff --git a/lib/mv/constants.ex b/lib/mv/constants.ex
index 4ef355d..de429e8 100644
--- a/lib/mv/constants.ex
+++ b/lib/mv/constants.ex
@@ -27,8 +27,26 @@ defmodule Mv.Constants do
 
   @email_validator_checks [:html_input, :pow]
 
+  # Member fields that are required when Vereinfacht integration is active (contact sync)
+  @vereinfacht_required_member_fields [:first_name, :last_name, :street, :postal_code, :city]
+
   def member_fields, do: @member_fields
 
+  @doc """
+  Returns member fields that are always required when Vereinfacht integration is configured.
+
+  Used for validation, member form required indicators, and settings UI (checkbox disabled).
+  """
+  def vereinfacht_required_member_fields, do: @vereinfacht_required_member_fields
+
+  @doc """
+  Returns whether the given member field is required by Vereinfacht when integration is active.
+  """
+  def vereinfacht_required_field?(field) when is_atom(field),
+    do: field in @vereinfacht_required_member_fields
+
+  def vereinfacht_required_field?(_), do: false
+
   @doc """
   Returns the prefix used for custom field keys in field visibility maps.
 
diff --git a/lib/mv_web/components/core_components.ex b/lib/mv_web/components/core_components.ex
index 40cb800..21e3546 100644
--- a/lib/mv_web/components/core_components.ex
+++ b/lib/mv_web/components/core_components.ex
@@ -448,6 +448,8 @@ defmodule MvWeb.CoreComponents do
   end
 
   def input(%{type: "select"} = assigns) do
+    assigns = ensure_aria_required_for_input(assigns)
+
     ~H"""
     <fieldset class="mb-2 fieldset">
       <label>
@@ -475,6 +477,8 @@ defmodule MvWeb.CoreComponents do
   end
 
   def input(%{type: "textarea"} = assigns) do
+    assigns = ensure_aria_required_for_input(assigns)
+
     ~H"""
     <fieldset class="mb-2 fieldset">
       <label>
@@ -502,6 +506,8 @@ defmodule MvWeb.CoreComponents do
 
   # All other inputs text, datetime-local, url, password, etc. are handled here...
   def input(assigns) do
+    assigns = ensure_aria_required_for_input(assigns)
+
     ~H"""
     <fieldset class="mb-2 fieldset">
       <label>
@@ -529,6 +535,18 @@ defmodule MvWeb.CoreComponents do
     """
   end
 
+  # WCAG 2.1: set aria-required when required is true so screen readers announce required state
+  defp ensure_aria_required_for_input(assigns) do
+    rest = assigns.rest || %{}
+
+    rest =
+      if rest[:required],
+        do: Map.put(rest, :aria_required, "true"),
+        else: rest
+
+    assign(assigns, :rest, rest)
+  end
+
   # Helper used by inputs to generate form errors
   defp error(assigns) do
     ~H"""
diff --git a/lib/mv_web/live/member_field_live/form_component.ex b/lib/mv_web/live/member_field_live/form_component.ex
index 1bba048..ae9e239 100644
--- a/lib/mv_web/live/member_field_live/form_component.ex
+++ b/lib/mv_web/live/member_field_live/form_component.ex
@@ -16,8 +16,8 @@ defmodule MvWeb.MemberFieldLive.FormComponent do
   - `on_cancel` - Callback function to call when form is cancelled
 
   ## Note
-  Member fields are technical fields that cannot be changed (name, value_type, description, required).
-  Only the visibility (show_in_overview) can be modified.
+  Member fields are technical fields that cannot be changed (name, value_type).
+  Visibility (show_in_overview) and required flag are stored in Settings and can be modified.
   """
   use MvWeb, :live_component
 
@@ -27,14 +27,13 @@ defmodule MvWeb.MemberFieldLive.FormComponent do
   alias MvWeb.Helpers.FieldTypeFormatter
   alias MvWeb.Translations.MemberFields
 
-  @required_fields [:first_name, :last_name, :email]
-
   @impl true
   def render(assigns) do
     assigns =
       assigns
       |> assign(:field_attributes, get_field_attributes(assigns.member_field))
       |> assign(:is_email_field?, assigns.member_field == :email)
+      |> assign(:vereinfacht_required_field?, vereinfacht_required_field?(assigns))
       |> assign(:field_label, MemberFields.label(assigns.member_field))
 
     ~H"""
@@ -117,89 +116,64 @@ defmodule MvWeb.MemberFieldLive.FormComponent do
             </fieldset>
           </div>
 
-          <div
-            :if={@is_email_field?}
-            class="tooltip tooltip-right"
-            data-tip={gettext("This is a technical field and cannot be changed")}
-            aria-label={gettext("This is a technical field and cannot be changed")}
-          >
-            <fieldset class="mb-2 fieldset">
-              <label>
-                <span class="mb-1 label flex items-center gap-2">
-                  {gettext("Description")}
-                  <.icon
-                    name="hero-information-circle"
-                    class="w-4 h-4 text-base-content/60 cursor-help"
-                    aria-hidden="true"
-                  />
-                </span>
-                <input
-                  type="text"
-                  name={@form[:description].name}
-                  id={@form[:description].id}
-                  value={@form[:description].value}
-                  disabled
-                  readonly
-                  class="w-full input"
-                />
-              </label>
-            </fieldset>
-          </div>
-          <.input
-            :if={not @is_email_field?}
-            field={@form[:description]}
-            type="text"
-            label={gettext("Description")}
-            disabled={@is_email_field?}
-            readonly={@is_email_field?}
-          />
-
-          <div
-            :if={@is_email_field?}
-            class="tooltip tooltip-right"
-            data-tip={gettext("This is a technical field and cannot be changed")}
-            aria-label={gettext("This is a technical field and cannot be changed")}
-          >
-            <fieldset class="mb-2 fieldset">
-              <label>
-                <input type="hidden" name={@form[:required].name} value="false" disabled />
-                <span class="label flex items-center gap-2">
-                  <input
-                    type="checkbox"
-                    name={@form[:required].name}
-                    id={@form[:required].id}
-                    value="true"
-                    checked={@form[:required].value}
-                    disabled
-                    readonly
-                    class="checkbox checkbox-sm"
-                  />
-                  <span class="flex items-center gap-2">
-                    {gettext("Required")}
-                    <.icon
-                      name="hero-information-circle"
-                      class="w-4 h-4 text-base-content/60 cursor-help"
-                      aria-hidden="true"
+          <%!-- Line break before Required / Show in overview block --%>
+          <div class="mt-4">
+            <%!-- Required: disabled for email (always required) or Vereinfacht-required fields when integration is active --%>
+            <div
+              :if={@is_email_field? or @vereinfacht_required_field?}
+              class="tooltip tooltip-right"
+              data-tip={
+                if(@is_email_field?,
+                  do: gettext("This is a technical field and cannot be changed"),
+                  else: gettext("Required for Vereinfacht integration and cannot be disabled.")
+                )
+              }
+              aria-label={
+                if(@is_email_field?,
+                  do: gettext("This is a technical field and cannot be changed"),
+                  else: gettext("Required for Vereinfacht integration and cannot be disabled.")
+                )
+              }
+            >
+              <fieldset class="mb-2 fieldset">
+                <label>
+                  <input type="hidden" name={@form[:required].name} value="true" />
+                  <span class="label flex items-center gap-2">
+                    <input
+                      type="checkbox"
+                      name={@form[:required].name}
+                      id={@form[:required].id}
+                      value="true"
+                      checked={@form[:required].value}
+                      disabled
+                      readonly
+                      class="checkbox checkbox-sm"
                     />
+                    <span class="flex items-center gap-2">
+                      {gettext("Required")}
+                      <.icon
+                        name="hero-information-circle"
+                        class="w-4 h-4 text-base-content/60 cursor-help"
+                        aria-hidden="true"
+                      />
+                    </span>
                   </span>
-                </span>
-              </label>
-            </fieldset>
-          </div>
-          <.input
-            :if={not @is_email_field?}
-            field={@form[:required]}
-            type="checkbox"
-            label={gettext("Required")}
-            disabled={@is_email_field?}
-            readonly={@is_email_field?}
-          />
+                </label>
+              </fieldset>
+            </div>
+            <.input
+              :if={not @is_email_field? and not @vereinfacht_required_field?}
+              field={@form[:required]}
+              type="checkbox"
+              label={gettext("Required")}
+            />
 
-          <.input
-            field={@form[:show_in_overview]}
-            type="checkbox"
-            label={gettext("Show in overview")}
-          />
+            <.input
+              field={@form[:show_in_overview]}
+              type="checkbox"
+              label={gettext("Show in overview")}
+            />
+          </div>
 
           <div class="justify-end mt-4 card-actions">
             <.button type="button" phx-click="cancel" phx-target={@myself}>
@@ -225,24 +199,35 @@ defmodule MvWeb.MemberFieldLive.FormComponent do
 
   @impl true
   def handle_event("validate", %{"member_field" => member_field_params}, socket) do
-    # For member fields, we only validate show_in_overview
-    # Other fields are read-only or derived from the Member Resource
     form = socket.assigns.form
-
-    updated_params =
-      member_field_params
-      |> Map.put(
-        "show_in_overview",
+    # Unchecked checkboxes are not in params; preserve current form value when key is missing
+    show_in_overview =
+      if Map.has_key?(member_field_params, "show_in_overview") do
         TypeParsers.parse_boolean(member_field_params["show_in_overview"])
-      )
-      |> Map.put("name", form.source["name"])
-      |> Map.put("value_type", form.source["value_type"])
-      |> Map.put("description", form.source["description"])
-      |> Map.put("required", form.source["required"])
+      else
+        form.source["show_in_overview"]
+      end
+
+    required =
+      socket.assigns.vereinfacht_required_field? ||
+        if Map.has_key?(member_field_params, "required") do
+          TypeParsers.parse_boolean(member_field_params["required"])
+        else
+          form.source["required"]
+        end
+
+    # Merge so we keep name/value_type and have current checkbox state; use as new form source
+    merged_source =
+      form.source
+      |> Map.merge(%{
+        "show_in_overview" => show_in_overview,
+        "required" => required,
+        "name" => form.source["name"],
+        "value_type" => form.source["value_type"]
+      })
 
     updated_form =
-      form
-      |> Map.put(:value, updated_params)
+      to_form(merged_source, as: "member_field")
       |> Map.put(:errors, [])
 
     {:noreply, assign(socket, form: updated_form)}
@@ -250,23 +235,36 @@ defmodule MvWeb.MemberFieldLive.FormComponent do
 
   @impl true
   def handle_event("save", %{"member_field" => member_field_params}, socket) do
-    # Only show_in_overview can be changed for member fields
-    show_in_overview = TypeParsers.parse_boolean(member_field_params["show_in_overview"])
+    form = socket.assigns.form
+    # Unchecked checkboxes are not in submit params; use form source when key missing
+    show_in_overview =
+      if Map.has_key?(member_field_params, "show_in_overview") do
+        TypeParsers.parse_boolean(member_field_params["show_in_overview"])
+      else
+        form.source["show_in_overview"]
+      end
+
+    required =
+      socket.assigns.vereinfacht_required_field? ||
+        if Map.has_key?(member_field_params, "required") do
+          TypeParsers.parse_boolean(member_field_params["required"])
+        else
+          form.source["required"]
+        end
+
     field_string = Atom.to_string(socket.assigns.member_field)
 
-    # Use atomic action to update only this single field
-    # This prevents lost updates in concurrent scenarios
-    case Membership.update_single_member_field_visibility(
+    case Membership.update_single_member_field(
            socket.assigns.settings,
            field: field_string,
-           show_in_overview: show_in_overview
+           show_in_overview: show_in_overview,
+           required: required
          ) do
       {:ok, _updated_settings} ->
         socket.assigns.on_save.(socket.assigns.member_field, "update")
         {:noreply, socket}
 
       {:error, error} ->
-        # Add error to form
         form =
           socket.assigns.form
           |> Map.put(:errors, [
@@ -288,16 +286,29 @@ defmodule MvWeb.MemberFieldLive.FormComponent do
   defp assign_form(%{assigns: %{member_field: member_field, settings: settings}} = socket) do
     field_attributes = get_field_attributes(member_field)
     visibility_config = settings.member_field_visibility || %{}
-    normalized_config = VisibilityConfig.normalize(visibility_config)
-    show_in_overview = Map.get(normalized_config, member_field, true)
+    required_config = settings.member_field_required || %{}
+    normalized_visibility = VisibilityConfig.normalize(visibility_config)
+    normalized_required = VisibilityConfig.normalize(required_config)
+    show_in_overview = Map.get(normalized_visibility, member_field, true)
+    vereinfacht_required? = Mv.Config.vereinfacht_configured?()
+    # Persist in socket so validate/save can enforce server-side without relying on render assigns
+    socket =
+      assign(
+        socket,
+        :vereinfacht_required_field?,
+        vereinfacht_required_field?(%{member_field: member_field})
+      )
+
+    # Email always required; Vereinfacht-required fields when integration active; else from settings
+    required =
+      member_field == :email ||
+        (vereinfacht_required? && Mv.Constants.vereinfacht_required_field?(member_field)) ||
+        Map.get(normalized_required, member_field, false)
 
-    # Create a manual form structure with string keys
-    # Note: immutable is not included as it's not editable for member fields
     form_data = %{
       "name" => MemberFields.label(member_field),
       "value_type" => FieldTypeFormatter.format(field_attributes.value_type),
-      "description" => field_attributes.description || "",
-      "required" => field_attributes.required,
+      "required" => required,
       "show_in_overview" => show_in_overview
     }
 
@@ -307,24 +318,14 @@ defmodule MvWeb.MemberFieldLive.FormComponent do
   end
 
   defp get_field_attributes(field) when is_atom(field) do
-    # Get attribute info from Member Resource
     alias Ash.Resource.Info
 
     case Info.attribute(Mv.Membership.Member, field) do
       nil ->
-        # Fallback for fields not in resource (shouldn't happen with Constants)
-        %{
-          value_type: :string,
-          description: nil,
-          required: field in @required_fields
-        }
+        %{value_type: :string}
 
       attribute ->
-        %{
-          value_type: attribute.type,
-          description: nil,
-          required: not attribute.allow_nil?
-        }
+        %{value_type: attribute.type}
     end
   end
 
@@ -335,4 +336,9 @@ defmodule MvWeb.MemberFieldLive.FormComponent do
   defp format_error(error) do
     inspect(error)
   end
+
+  defp vereinfacht_required_field?(assigns) do
+    Mv.Config.vereinfacht_configured?() &&
+      Mv.Constants.vereinfacht_required_field?(assigns.member_field)
+  end
 end
diff --git a/lib/mv_web/live/member_field_live/index_component.ex b/lib/mv_web/live/member_field_live/index_component.ex
index 5204030..db62778 100644
--- a/lib/mv_web/live/member_field_live/index_component.ex
+++ b/lib/mv_web/live/member_field_live/index_component.ex
@@ -22,7 +22,6 @@ defmodule MvWeb.MemberFieldLive.IndexComponent do
     assigns =
       assigns
       |> assign(:member_fields, get_member_fields_with_visibility(assigns.settings))
-      |> assign(:required?, &required?/1)
 
     ~H"""
     <div id={@id}>
@@ -62,22 +61,15 @@ defmodule MvWeb.MemberFieldLive.IndexComponent do
           {format_value_type(field_data.field)}
         </:col>
 
-        <:col :let={{_field_name, field_data}} label={gettext("Description")}>
-          {field_data.description || ""}
-        </:col>
-
         <:col
           :let={{_field_name, field_data}}
           label={gettext("Required")}
           class="max-w-[9.375rem] text-center"
         >
-          <span
-            :if={@required?.(field_data.field)}
-            class="text-base-content font-semibold"
-          >
+          <span :if={field_data.required} class="text-base-content font-semibold">
             {gettext("Required")}
           </span>
-          <span :if={!@required?.(field_data.field)} class="text-base-content/70">
+          <span :if={!field_data.required} class="text-base-content/70">
             {gettext("Optional")}
           </span>
         </:col>
@@ -173,26 +165,35 @@ defmodule MvWeb.MemberFieldLive.IndexComponent do
       {:error, _} ->
         # Return a minimal struct-like map for fallback
         # This is only used for initial rendering, actual settings will be loaded properly
-        %{member_field_visibility: %{}}
+        %{member_field_visibility: %{}, member_field_required: %{}}
     end
   end
 
   defp get_member_fields_with_visibility(settings) do
     member_fields = Mv.Constants.member_fields()
     visibility_config = settings.member_field_visibility || %{}
+    required_config = settings.member_field_required || %{}
+    vereinfacht_required? = Mv.Config.vereinfacht_configured?()
 
-    # Normalize visibility config keys to atoms
-    normalized_config = VisibilityConfig.normalize(visibility_config)
+    normalized_visibility = VisibilityConfig.normalize(visibility_config)
+    normalized_required = VisibilityConfig.normalize(required_config)
 
     Enum.map(member_fields, fn field ->
-      show_in_overview = Map.get(normalized_config, field, true)
+      show_in_overview = Map.get(normalized_visibility, field, true)
+
+      # Email always required; Vereinfacht-required fields when integration active; else from settings
+      required =
+        field == :email ||
+          (vereinfacht_required? && Mv.Constants.vereinfacht_required_field?(field)) ||
+          Map.get(normalized_required, field, false)
+
       attribute = Info.attribute(Mv.Membership.Member, field)
 
       %{
         field: field,
         show_in_overview: show_in_overview,
-        value_type: (attribute && attribute.type) || :string,
-        description: nil
+        required: required,
+        value_type: (attribute && attribute.type) || :string
       }
     end)
     |> Enum.map(fn field_data ->
@@ -206,14 +207,4 @@ defmodule MvWeb.MemberFieldLive.IndexComponent do
       attribute -> FieldTypeFormatter.format(attribute.type)
     end
   end
-
-  # Check if a field is required by checking the actual attribute definition
-  defp required?(field) when is_atom(field) do
-    case Info.attribute(Mv.Membership.Member, field) do
-      nil -> false
-      attribute -> not attribute.allow_nil?
-    end
-  end
-
-  defp required?(_), do: false
 end
diff --git a/lib/mv_web/live/member_live/form.ex b/lib/mv_web/live/member_live/form.ex
index 7c138c4..6b3ce67 100644
--- a/lib/mv_web/live/member_live/form.ex
+++ b/lib/mv_web/live/member_live/form.ex
@@ -23,6 +23,8 @@ defmodule MvWeb.MemberLive.Form do
 
   import MvWeb.LiveHelpers, only: [current_actor: 1, submit_form: 3]
 
+  alias Mv.Membership
+  alias Mv.Membership.Helpers.VisibilityConfig
   alias Mv.MembershipFees
   alias Mv.MembershipFees.MembershipFeeType
   alias MvWeb.Helpers.MembershipFeeHelpers
@@ -84,30 +86,54 @@ defmodule MvWeb.MemberLive.Form do
                 <%!-- Name Row --%>
                 <div class="flex gap-4">
                   <div class="w-48">
-                    <.input field={@form[:first_name]} label={gettext("First Name")} />
+                    <.input
+                      field={@form[:first_name]}
+                      label={gettext("First Name")}
+                      required={@member_field_required_map[:first_name]}
+                    />
                   </div>
                   <div class="w-48">
-                    <.input field={@form[:last_name]} label={gettext("Last Name")} />
+                    <.input
+                      field={@form[:last_name]}
+                      label={gettext("Last Name")}
+                      required={@member_field_required_map[:last_name]}
+                    />
                   </div>
                 </div>
 
                 <%!-- Address Row --%>
                 <div class="flex gap-4">
                   <div class="flex-1">
-                    <.input field={@form[:street]} label={gettext("Street")} />
+                    <.input
+                      field={@form[:street]}
+                      label={gettext("Street")}
+                      required={@member_field_required_map[:street]}
+                    />
                   </div>
                   <div class="w-16">
-                    <.input field={@form[:house_number]} label={gettext("Nr.")} />
+                    <.input
+                      field={@form[:house_number]}
+                      label={gettext("Nr.")}
+                      required={@member_field_required_map[:house_number]}
+                    />
                   </div>
                   <div class="w-24">
-                    <.input field={@form[:postal_code]} label={gettext("Postal Code")} />
+                    <.input
+                      field={@form[:postal_code]}
+                      label={gettext("Postal Code")}
+                      required={@member_field_required_map[:postal_code]}
+                    />
                   </div>
                   <div class="w-32">
-                    <.input field={@form[:city]} label={gettext("City")} />
+                    <.input
+                      field={@form[:city]}
+                      label={gettext("City")}
+                      required={@member_field_required_map[:city]}
+                    />
                   </div>
                 </div>
 
-                <%!-- Email --%>
+                <%!-- Email (always required) --%>
                 <div>
                   <.input field={@form[:email]} label={gettext("Email")} required type="email" />
                 </div>
@@ -115,16 +141,31 @@ defmodule MvWeb.MemberLive.Form do
                 <%!-- Membership Dates Row --%>
                 <div class="flex gap-4">
                   <div class="w-36">
-                    <.input field={@form[:join_date]} label={gettext("Join Date")} type="date" />
+                    <.input
+                      field={@form[:join_date]}
+                      label={gettext("Join Date")}
+                      type="date"
+                      required={@member_field_required_map[:join_date]}
+                    />
                   </div>
                   <div class="w-36">
-                    <.input field={@form[:exit_date]} label={gettext("Exit Date")} type="date" />
+                    <.input
+                      field={@form[:exit_date]}
+                      label={gettext("Exit Date")}
+                      type="date"
+                      required={@member_field_required_map[:exit_date]}
+                    />
                   </div>
                 </div>
 
                 <%!-- Notes --%>
                 <div>
-                  <.input field={@form[:notes]} label={gettext("Notes")} type="textarea" />
+                  <.input
+                    field={@form[:notes]}
+                    label={gettext("Notes")}
+                    type="textarea"
+                    required={@member_field_required_map[:notes]}
+                  />
                 </div>
               </div>
             </.form_section>
@@ -254,6 +295,9 @@ defmodule MvWeb.MemberLive.Form do
     # Load available membership fee types
     available_fee_types = load_available_fee_types(member, actor)
 
+    # Load settings to know which member fields are required (for asterisk/tooltip)
+    member_field_required_map = get_member_field_required_map()
+
     {:ok,
      socket
      |> assign(:return_to, return_to(params["return_to"]))
@@ -263,9 +307,38 @@ defmodule MvWeb.MemberLive.Form do
      |> assign(:page_title, page_title)
      |> assign(:available_fee_types, available_fee_types)
      |> assign(:interval_warning, nil)
+     |> assign(:member_field_required_map, member_field_required_map)
      |> assign_form()}
   end
 
+  defp get_member_field_required_map do
+    vereinfacht_required? = Mv.Config.vereinfacht_configured?()
+
+    case Membership.get_settings() do
+      {:ok, settings} ->
+        required_config = settings.member_field_required || %{}
+        normalized = VisibilityConfig.normalize(required_config)
+
+        Mv.Constants.member_fields()
+        |> Enum.map(fn field ->
+          required =
+            field == :email ||
+              (vereinfacht_required? && Mv.Constants.vereinfacht_required_field?(field)) ||
+              Map.get(normalized, field, false)
+
+          {field, required}
+        end)
+        |> Map.new()
+
+      {:error, _} ->
+        # Email always required; Vereinfacht fields when integration active
+        Map.new(Mv.Constants.member_fields(), fn f ->
+          {f,
+           f == :email || (vereinfacht_required? && Mv.Constants.vereinfacht_required_field?(f))}
+        end)
+    end
+  end
+
   defp return_to("show"), do: "show"
   defp return_to(_), do: "index"
 
diff --git a/priv/gettext/de/LC_MESSAGES/default.po b/priv/gettext/de/LC_MESSAGES/default.po
index d39d86b..c418dca 100644
--- a/priv/gettext/de/LC_MESSAGES/default.po
+++ b/priv/gettext/de/LC_MESSAGES/default.po
@@ -287,8 +287,6 @@ msgstr "Abbrechen"
 #: lib/mv_web/live/group_live/form.ex
 #: lib/mv_web/live/group_live/index.ex
 #: lib/mv_web/live/group_live/show.ex
-#: lib/mv_web/live/member_field_live/form_component.ex
-#: lib/mv_web/live/member_field_live/index_component.ex
 #: lib/mv_web/live/membership_fee_type_live/form.ex
 #: lib/mv_web/live/role_live/form.ex
 #: lib/mv_web/live/role_live/index.html.heex
@@ -2911,3 +2909,8 @@ msgstr "Okt."
 #, elixir-autogen, elixir-format
 msgid "Sep."
 msgstr "Sep."
+
+#: lib/mv_web/live/member_field_live/form_component.ex
+#, elixir-autogen, elixir-format
+msgid "Required for Vereinfacht integration and cannot be disabled."
+msgstr "Für die Vereinfacht-Integration erforderlich und kann nicht deaktiviert werden."
diff --git a/priv/gettext/default.pot b/priv/gettext/default.pot
index ff466ab..2e7e480 100644
--- a/priv/gettext/default.pot
+++ b/priv/gettext/default.pot
@@ -288,8 +288,6 @@ msgstr ""
 #: lib/mv_web/live/group_live/form.ex
 #: lib/mv_web/live/group_live/index.ex
 #: lib/mv_web/live/group_live/show.ex
-#: lib/mv_web/live/member_field_live/form_component.ex
-#: lib/mv_web/live/member_field_live/index_component.ex
 #: lib/mv_web/live/membership_fee_type_live/form.ex
 #: lib/mv_web/live/role_live/form.ex
 #: lib/mv_web/live/role_live/index.html.heex
@@ -2911,3 +2909,8 @@ msgstr ""
 #, elixir-autogen, elixir-format
 msgid "Sep."
 msgstr ""
+
+#: lib/mv_web/live/member_field_live/form_component.ex
+#, elixir-autogen, elixir-format
+msgid "Required for Vereinfacht integration and cannot be disabled."
+msgstr ""
diff --git a/priv/gettext/en/LC_MESSAGES/default.po b/priv/gettext/en/LC_MESSAGES/default.po
index e5e0181..3c53a7e 100644
--- a/priv/gettext/en/LC_MESSAGES/default.po
+++ b/priv/gettext/en/LC_MESSAGES/default.po
@@ -288,8 +288,6 @@ msgstr ""
 #: lib/mv_web/live/group_live/form.ex
 #: lib/mv_web/live/group_live/index.ex
 #: lib/mv_web/live/group_live/show.ex
-#: lib/mv_web/live/member_field_live/form_component.ex
-#: lib/mv_web/live/member_field_live/index_component.ex
 #: lib/mv_web/live/membership_fee_type_live/form.ex
 #: lib/mv_web/live/role_live/form.ex
 #: lib/mv_web/live/role_live/index.html.heex
@@ -2911,3 +2909,8 @@ msgstr ""
 #, elixir-autogen, elixir-format
 msgid "Sep."
 msgstr ""
+
+#: lib/mv_web/live/member_field_live/form_component.ex
+#, elixir-autogen, elixir-format
+msgid "Required for Vereinfacht integration and cannot be disabled."
+msgstr "Required for Vereinfacht integration and cannot be disabled."
diff --git a/priv/repo/migrations/20260223195453_add_member_field_required_to_settings.exs b/priv/repo/migrations/20260223195453_add_member_field_required_to_settings.exs
new file mode 100644
index 0000000..b6696fe
--- /dev/null
+++ b/priv/repo/migrations/20260223195453_add_member_field_required_to_settings.exs
@@ -0,0 +1,21 @@
+defmodule Mv.Repo.Migrations.AddMemberFieldRequiredToSettings do
+  @moduledoc """
+  Updates resources based on their most recent snapshots.
+
+  This file was autogenerated with `mix ash_postgres.generate_migrations`
+  """
+
+  use Ecto.Migration
+
+  def up do
+    alter table(:settings) do
+      add :member_field_required, :map
+    end
+  end
+
+  def down do
+    alter table(:settings) do
+      remove :member_field_required
+    end
+  end
+end
diff --git a/priv/resource_snapshots/repo/settings/20260223195453.json b/priv/resource_snapshots/repo/settings/20260223195453.json
new file mode 100644
index 0000000..e035389
--- /dev/null
+++ b/priv/resource_snapshots/repo/settings/20260223195453.json
@@ -0,0 +1,152 @@
+{
+  "attributes": [
+    {
+      "allow_nil?": false,
+      "default": "fragment(\"gen_random_uuid()\")",
+      "generated?": false,
+      "precision": null,
+      "primary_key?": true,
+      "references": null,
+      "scale": null,
+      "size": null,
+      "source": "id",
+      "type": "uuid"
+    },
+    {
+      "allow_nil?": false,
+      "default": "nil",
+      "generated?": false,
+      "precision": null,
+      "primary_key?": false,
+      "references": null,
+      "scale": null,
+      "size": null,
+      "source": "club_name",
+      "type": "text"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "precision": null,
+      "primary_key?": false,
+      "references": null,
+      "scale": null,
+      "size": null,
+      "source": "member_field_visibility",
+      "type": "map"
+    },
+    {
+      "allow_nil?": false,
+      "default": "true",
+      "generated?": false,
+      "precision": null,
+      "primary_key?": false,
+      "references": null,
+      "scale": null,
+      "size": null,
+      "source": "include_joining_cycle",
+      "type": "boolean"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "precision": null,
+      "primary_key?": false,
+      "references": null,
+      "scale": null,
+      "size": null,
+      "source": "default_membership_fee_type_id",
+      "type": "uuid"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "precision": null,
+      "primary_key?": false,
+      "references": null,
+      "scale": null,
+      "size": null,
+      "source": "vereinfacht_api_url",
+      "type": "text"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "precision": null,
+      "primary_key?": false,
+      "references": null,
+      "scale": null,
+      "size": null,
+      "source": "vereinfacht_api_key",
+      "type": "text"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "precision": null,
+      "primary_key?": false,
+      "references": null,
+      "scale": null,
+      "size": null,
+      "source": "vereinfacht_club_id",
+      "type": "text"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "precision": null,
+      "primary_key?": false,
+      "references": null,
+      "scale": null,
+      "size": null,
+      "source": "vereinfacht_app_url",
+      "type": "text"
+    },
+    {
+      "allow_nil?": false,
+      "default": "fragment(\"(now() AT TIME ZONE 'utc')\")",
+      "generated?": false,
+      "precision": null,
+      "primary_key?": false,
+      "references": null,
+      "scale": null,
+      "size": null,
+      "source": "inserted_at",
+      "type": "utc_datetime_usec"
+    },
+    {
+      "allow_nil?": false,
+      "default": "fragment(\"(now() AT TIME ZONE 'utc')\")",
+      "generated?": false,
+      "precision": null,
+      "primary_key?": false,
+      "references": null,
+      "scale": null,
+      "size": null,
+      "source": "updated_at",
+      "type": "utc_datetime_usec"
+    }
+  ],
+  "base_filter": null,
+  "check_constraints": [],
+  "create_table_options": null,
+  "custom_indexes": [],
+  "custom_statements": [],
+  "has_create_action": true,
+  "hash": "4C29CEF273C1180162E7231A7F7CCE5DABD035E121648E48B6FBE30AE5191FF0",
+  "identities": [],
+  "multitenancy": {
+    "attribute": null,
+    "global": null,
+    "strategy": null
+  },
+  "repo": "Elixir.Mv.Repo",
+  "schema": null,
+  "table": "settings"
+}
diff --git a/test/membership/member_test.exs b/test/membership/member_test.exs
index 705ab61..676db71 100644
--- a/test/membership/member_test.exs
+++ b/test/membership/member_test.exs
@@ -92,6 +92,66 @@ defmodule Mv.Membership.MemberTest do
     end
   end
 
+  describe "Settings-driven required fields" do
+    @valid_attrs %{
+      first_name: "John",
+      last_name: "Doe",
+      email: "john@example.com"
+    }
+
+    setup do
+      {:ok, settings} = Membership.get_settings()
+      saved_visibility = settings.member_field_visibility || %{}
+      saved_required = settings.member_field_required || %{}
+
+      on_exit(fn ->
+        {:ok, s} = Membership.get_settings()
+
+        Membership.update_settings(s, %{
+          member_field_visibility: saved_visibility,
+          member_field_required: saved_required
+        })
+      end)
+
+      :ok
+    end
+
+    test "when first_name is required in settings, create without first_name fails", %{
+      actor: actor
+    } do
+      {:ok, settings} = Membership.get_settings()
+
+      {:ok, _} =
+        Membership.update_single_member_field(settings,
+          field: "first_name",
+          show_in_overview: true,
+          required: true
+        )
+
+      attrs = Map.delete(@valid_attrs, :first_name)
+
+      assert {:error, %Ash.Error.Invalid{errors: errors}} =
+               Membership.create_member(attrs, actor: actor)
+
+      assert error_message(errors, :first_name) =~ "can't be blank"
+    end
+
+    test "when first_name is required in settings, create with first_name succeeds", %{
+      actor: actor
+    } do
+      {:ok, settings} = Membership.get_settings()
+
+      {:ok, _} =
+        Membership.update_single_member_field(settings,
+          field: "first_name",
+          show_in_overview: true,
+          required: true
+        )
+
+      assert {:ok, _member} = Membership.create_member(@valid_attrs, actor: actor)
+    end
+  end
+
   describe "Authorization" do
     @valid_attrs %{
       first_name: "John",
diff --git a/test/membership/setting_test.exs b/test/membership/setting_test.exs
index 531ab88..f892161 100644
--- a/test/membership/setting_test.exs
+++ b/test/membership/setting_test.exs
@@ -3,6 +3,23 @@ defmodule Mv.Membership.SettingTest do
   alias Mv.Membership
 
   describe "Settings Resource" do
+    setup do
+      {:ok, settings} = Membership.get_settings()
+      saved_visibility = settings.member_field_visibility || %{}
+      saved_required = settings.member_field_required || %{}
+
+      on_exit(fn ->
+        {:ok, s} = Membership.get_settings()
+
+        Membership.update_settings(s, %{
+          member_field_visibility: saved_visibility,
+          member_field_required: saved_required
+        })
+      end)
+
+      :ok
+    end
+
     test "can read settings" do
       # Settings should be a singleton resource
       assert {:ok, _settings} = Membership.get_settings()
@@ -39,6 +56,65 @@ defmodule Mv.Membership.SettingTest do
 
       assert error_message(errors, :club_name) =~ "must be present"
     end
+
+    test "can update and read member_field_required" do
+      {:ok, settings} = Membership.get_settings()
+
+      required_config = %{"first_name" => true, "last_name" => true}
+
+      assert {:ok, updated} =
+               Membership.update_settings(settings, %{member_field_required: required_config})
+
+      assert updated.member_field_required["first_name"] == true
+      assert updated.member_field_required["last_name"] == true
+    end
+
+    test "member_field_required rejects invalid keys" do
+      {:ok, settings} = Membership.get_settings()
+
+      assert {:error, %Ash.Error.Invalid{errors: errors}} =
+               Membership.update_settings(settings, %{
+                 member_field_required: %{"invalid_field" => true}
+               })
+
+      assert error_message(errors, :member_field_required) =~ "Invalid member field"
+    end
+
+    test "member_field_required rejects non-boolean values" do
+      {:ok, settings} = Membership.get_settings()
+
+      assert {:error, %Ash.Error.Invalid{errors: errors}} =
+               Membership.update_settings(settings, %{
+                 member_field_required: %{"first_name" => "yes"}
+               })
+
+      assert error_message(errors, :member_field_required) =~ "must be booleans"
+    end
+
+    test "update_single_member_field updates both visibility and required" do
+      {:ok, settings} = Membership.get_settings()
+
+      assert {:ok, updated} =
+               Membership.update_single_member_field(settings,
+                 field: "first_name",
+                 show_in_overview: true,
+                 required: true
+               )
+
+      assert updated.member_field_visibility["first_name"] == true
+      assert updated.member_field_required["first_name"] == true
+
+      # Update same field to required: false
+      assert {:ok, updated2} =
+               Membership.update_single_member_field(updated,
+                 field: "first_name",
+                 show_in_overview: false,
+                 required: false
+               )
+
+      assert updated2.member_field_visibility["first_name"] == false
+      assert updated2.member_field_required["first_name"] == false
+    end
   end
 
   # Helper function to extract error messages
diff --git a/test/mv/vereinfacht/changes/sync_contact_test.exs b/test/mv/vereinfacht/changes/sync_contact_test.exs
index aa102a5..f1dbc9c 100644
--- a/test/mv/vereinfacht/changes/sync_contact_test.exs
+++ b/test/mv/vereinfacht/changes/sync_contact_test.exs
@@ -54,7 +54,10 @@ defmodule Mv.Vereinfacht.Changes.SyncContactTest do
       attrs = %{
         first_name: "API",
         last_name: "Test",
-        email: "api_test_#{System.unique_integer([:positive])}@example.com"
+        email: "api_test_#{System.unique_integer([:positive])}@example.com",
+        street: "Test St",
+        postal_code: "12345",
+        city: "Test City"
       }
 
       assert {:ok, member} = Membership.create_member(attrs, actor: system_actor)
@@ -66,7 +69,14 @@ defmodule Mv.Vereinfacht.Changes.SyncContactTest do
 
     test "update_member succeeds and after_transaction runs without error (API may fail)" do
       set_vereinfacht_env()
-      member = Mv.Fixtures.member_fixture()
+
+      member =
+        Mv.Fixtures.member_fixture(%{
+          street: "Test St",
+          postal_code: "12345",
+          city: "Test City"
+        })
+
       system_actor = Mv.Helpers.SystemActor.get_system_actor()
 
       assert {:ok, updated} =
diff --git a/test/mv_web/live/member_field_live/index_component_test.exs b/test/mv_web/live/member_field_live/index_component_test.exs
index 037a77c..6ad1627 100644
--- a/test/mv_web/live/member_field_live/index_component_test.exs
+++ b/test/mv_web/live/member_field_live/index_component_test.exs
@@ -5,8 +5,8 @@ defmodule MvWeb.MemberFieldLive.IndexComponentTest do
   Tests cover:
   - Rendering all member fields from Mv.Constants.member_fields()
   - Displaying show_in_overview status as badge (Yes/No)
-  - Displaying required status for required fields (first_name, last_name, email)
-  - Current status is displayed based on settings.member_field_visibility
+  - Displaying required status from settings.member_field_required (email is always required)
+  - Current status is displayed based on settings.member_field_visibility and member_field_required
   - Default status is "Yes" (visible) when not configured in settings
   """
   use MvWeb.ConnCase, async: false
@@ -45,11 +45,10 @@ defmodule MvWeb.MemberFieldLive.IndexComponentTest do
       assert html =~ "badge" or html =~ "Yes" or html =~ "No"
     end
 
-    test "displays required status for required fields", %{conn: conn} do
+    test "displays required status column", %{conn: conn} do
       {:ok, _view, html} = live(conn, ~p"/settings")
 
-      # Required fields: first_name, last_name, email
-      # Should have "Required" column or indicator
+      # Should have "Required" column; email is always required
       assert html =~ "Required" or html =~ "required"
     end
 
@@ -85,40 +84,54 @@ defmodule MvWeb.MemberFieldLive.IndexComponentTest do
   end
 
   describe "required fields" do
-    test "marks first_name as required", %{conn: conn} do
-      {:ok, _view, html} = live(conn, ~p"/settings")
+    setup do
+      {:ok, settings} = Membership.get_settings()
+      saved_visibility = settings.member_field_visibility || %{}
+      saved_required = settings.member_field_required || %{}
 
-      # first_name should be marked as required
-      assert html =~ "first_name" or html =~ "First name"
-      # Should have required indicator
-      assert html =~ "required" or html =~ "Required"
+      on_exit(fn ->
+        {:ok, s} = Membership.get_settings()
+
+        Membership.update_settings(s, %{
+          member_field_visibility: saved_visibility,
+          member_field_required: saved_required
+        })
+      end)
+
+      :ok
     end
 
-    test "marks last_name as required", %{conn: conn} do
+    test "marks email as required (always from settings)", %{conn: conn} do
       {:ok, _view, html} = live(conn, ~p"/settings")
 
-      # last_name should be marked as required
-      assert html =~ "last_name" or html =~ "Last name"
-      # Should have required indicator
-      assert html =~ "required" or html =~ "Required"
-    end
-
-    test "marks email as required", %{conn: conn} do
-      {:ok, _view, html} = live(conn, ~p"/settings")
-
-      # email should be marked as required
+      # Email is always required
       assert html =~ "email" or html =~ "Email"
-      # Should have required indicator
-      assert html =~ "required" or html =~ "Required"
+      assert html =~ "Required" or html =~ "Optional"
     end
 
-    test "does not mark optional fields as required", %{conn: conn} do
+    test "when first_name is set required in settings, table shows Required", %{conn: conn} do
+      {:ok, settings} = Membership.get_settings()
+
+      {:ok, _} =
+        Membership.update_single_member_field(settings,
+          field: "first_name",
+          show_in_overview: true,
+          required: true
+        )
+
       {:ok, _view, html} = live(conn, ~p"/settings")
 
-      # Optional fields should not have required indicator
-      # Check that street (optional) doesn't have required badge
-      # This test verifies that only required fields show the indicator
-      assert html =~ "street" or html =~ "Street"
+      # First name row should show Required (and Optional for others)
+      assert html =~ "First name" or html =~ "first_name"
+      assert html =~ "Required"
+    end
+
+    test "optional fields show Optional when not required in settings", %{conn: conn} do
+      {:ok, _view, html} = live(conn, ~p"/settings")
+
+      # Email is required; other fields default to optional
+      assert html =~ "Optional"
+      assert html =~ "Required"
     end
   end
 end
diff --git a/test/mv_web/member_live/form_error_handling_test.exs b/test/mv_web/member_live/form_error_handling_test.exs
index 9e55cd8..d61d3fd 100644
--- a/test/mv_web/member_live/form_error_handling_test.exs
+++ b/test/mv_web/member_live/form_error_handling_test.exs
@@ -9,6 +9,23 @@ defmodule MvWeb.MemberLive.FormErrorHandlingTest do
   require Ash.Query
 
   describe "error handling - flash messages" do
+    setup do
+      {:ok, settings} = Mv.Membership.get_settings()
+      saved_visibility = settings.member_field_visibility || %{}
+      saved_required = settings.member_field_required || %{}
+
+      on_exit(fn ->
+        {:ok, s} = Mv.Membership.get_settings()
+
+        Mv.Membership.update_settings(s, %{
+          member_field_visibility: saved_visibility,
+          member_field_required: saved_required
+        })
+      end)
+
+      :ok
+    end
+
     @describetag :ui
     test "shows flash message when member creation fails with validation error", %{conn: conn} do
       system_actor = Mv.Helpers.SystemActor.get_system_actor()
@@ -74,6 +91,36 @@ defmodule MvWeb.MemberLive.FormErrorHandlingTest do
                html =~ "Please correct" or html =~ "Bitte korrigieren"
     end
 
+    @tag :ui
+    test "shows validation error when settings-required field is missing", %{conn: conn} do
+      {:ok, settings} = Mv.Membership.get_settings()
+
+      {:ok, _} =
+        Mv.Membership.update_single_member_field(settings,
+          field: "first_name",
+          show_in_overview: true,
+          required: true
+        )
+
+      conn = conn_with_oidc_user(conn)
+      {:ok, view, _html} = live(conn, "/members/new")
+
+      # Submit without first_name (required in settings)
+      form_data = %{
+        "member[last_name]" => "User",
+        "member[email]" => "newuser#{System.unique_integer([:positive])}@example.com"
+      }
+
+      html =
+        view
+        |> form("#member-form", form_data)
+        |> render_submit()
+
+      assert html =~ "error" or html =~ "Error" or html =~ "Fehler" or
+               html =~ "first_name" or html =~ "First name" or html =~ "can't be blank" or
+               html =~ "darf nicht leer sein"
+    end
+
     test "shows flash message when member update fails", %{conn: conn} do
       system_actor = Mv.Helpers.SystemActor.get_system_actor()