diff --git a/priv/repo/seeds.exs b/priv/repo/seeds.exs
index e96ca6e..6468949 100644
--- a/priv/repo/seeds.exs
+++ b/priv/repo/seeds.exs
@@ -3,10 +3,10 @@
 #     mix run priv/repo/seeds.exs
 #
 
-alias Mv.Membership
 alias Mv.Accounts
-alias Mv.MembershipFees.MembershipFeeType
+alias Mv.Membership
 alias Mv.MembershipFees.CycleGenerator
+alias Mv.MembershipFees.MembershipFeeType
 
 require Ash.Query
 
@@ -579,6 +579,39 @@ Enum.with_index(linked_members)
   end
 end)
 
+# Create example groups (idempotent: create only if name does not exist)
+group_configs = [
+  %{name: "Vorstand", description: "Gremium Vorstand"},
+  %{name: "Trainer*innen", description: "Alle lizenzierten Trainer*innen"},
+  %{name: "Jugend", description: "Jugendbereich"},
+  %{name: "Newsletter", description: "Empfänger*innen Newsletter"}
+]
+
+existing_groups =
+  case Membership.list_groups(actor: admin_user_with_role) do
+    {:ok, list} -> list
+    {:error, _} -> []
+  end
+
+existing_names_lower = MapSet.new(existing_groups, &String.downcase(&1.name))
+
+seed_groups =
+  Enum.reduce(group_configs, %{}, fn config, acc ->
+    name = config.name
+
+    if MapSet.member?(existing_names_lower, String.downcase(name)) do
+      group = Enum.find(existing_groups, &(String.downcase(&1.name) == String.downcase(name)))
+      Map.put(acc, name, group)
+    else
+      group =
+        Membership.create_group!(%{name: name, description: config.description},
+          actor: admin_user_with_role
+        )
+
+      Map.put(acc, name, group)
+    end
+  end)
+
 # Create sample custom field values for some members
 all_members = Ash.read!(Membership.Member, actor: admin_user_with_role)
 all_custom_fields = Ash.read!(Membership.CustomField, actor: admin_user_with_role)
@@ -587,6 +620,35 @@ all_custom_fields = Ash.read!(Membership.CustomField, actor: admin_user_with_rol
 find_field = fn name -> Enum.find(all_custom_fields, &(&1.name == name)) end
 find_member = fn email -> Enum.find(all_members, &(&1.email == email)) end
 
+# Assign seed members to groups (idempotent: duplicate create_member_group is skipped)
+member_group_assignments = [
+  {"hans.mueller@example.de", ["Vorstand", "Newsletter"]},
+  {"greta.schmidt@example.de", ["Jugend", "Newsletter"]},
+  {"friedrich.wagner@example.de", ["Trainer*innen"]},
+  {"maria.weber@example.de", ["Newsletter"]},
+  {"thomas.klein@example.de", ["Newsletter"]}
+]
+
+Enum.each(member_group_assignments, fn {email, group_names} ->
+  member = find_member.(email)
+
+  if member do
+    Enum.each(group_names, fn group_name ->
+      group = seed_groups[group_name]
+
+      if group do
+        case Membership.create_member_group(
+               %{member_id: member.id, group_id: group.id},
+               actor: admin_user_with_role
+             ) do
+          {:ok, _} -> :ok
+          {:error, _} -> :ok
+        end
+      end
+    end)
+  end
+end)
+
 # Add custom field values for Hans Müller
 if hans = find_member.("hans.mueller@example.de") do
   [
@@ -731,6 +793,7 @@ IO.puts(
 )
 
 IO.puts("   - Sample members: Hans, Greta, Friedrich")
+IO.puts("   - Groups: Vorstand, Trainer*innen, Jugend, Newsletter (with members assigned)")
 
 IO.puts(
   "   - Additional users: hans.mueller@example.de, greta.schmidt@example.de, maria.weber@example.de, thomas.klein@example.de"