diff --git a/auth.py b/auth.py
index f604ba1..7e2a06e 100644
--- a/auth.py
+++ b/auth.py
@@ -10,7 +10,7 @@ from fastapi_users import BaseUserManager, FastAPIUsers, UUIDIDMixin, schemas
 from fastapi_users.authentication import AuthenticationBackend, CookieTransport, JWTStrategy
 from fastapi_users.db import BaseUserDatabase
 
-from db import get_async_database_connection
+from db import get_async_database_connection, get_database_connection
 from templating import templates
 
 
@@ -19,7 +19,10 @@ SESSION_SECRET = os.environ.get("KUNDENPLATTFORM_SESSION_SECRET", "")
 COOKIE_NAME = "kundenplattform_session"
 COOKIE_MAX_AGE = 14 * 24 * 60 * 60  # 14 Tage, wie zuvor Starlettes SessionMiddleware-Default
 
-BENUTZER_SPALTEN = "id, organization_id, email, hashed_password, is_active, is_superuser, is_verified"
+BENUTZER_SPALTEN = (
+    "id, organization_id, email, hashed_password, is_active, is_superuser, "
+    "ist_organisationsadmin, is_verified"
+)
 
 
 @dataclass
@@ -30,16 +33,21 @@ class User:
     organization_id: uuid.UUID
     is_active: bool = True
     is_superuser: bool = False
+    ist_organisationsadmin: bool = False
     is_verified: bool = True
 
 
 class UserCreate(schemas.BaseUserCreate):
     organization_id: uuid.UUID
+    ist_organisationsadmin: Optional[bool] = False
     is_verified: Optional[bool] = True
 
 
 def _row_to_user(row) -> User:
-    user_id, organization_id, email, hashed_password, is_active, is_superuser, is_verified = row
+    (
+        user_id, organization_id, email, hashed_password, is_active,
+        is_superuser, ist_organisationsadmin, is_verified,
+    ) = row
 
     # psycopg liefert TEXT-Spalten hier teils als bytes zurück, nicht als str.
     if isinstance(hashed_password, bytes):
@@ -54,6 +62,7 @@ def _row_to_user(row) -> User:
         hashed_password=hashed_password,
         is_active=is_active,
         is_superuser=is_superuser,
+        ist_organisationsadmin=ist_organisationsadmin,
         is_verified=is_verified,
     )
 
@@ -86,8 +95,9 @@ class UserDatabase(BaseUserDatabase[User, uuid.UUID]):
             await cur.execute(
                 """
                 INSERT INTO benutzer
-                    (id, organization_id, email, hashed_password, is_active, is_superuser, is_verified)
-                VALUES (%s, %s, %s, %s, %s, %s, %s)
+                    (id, organization_id, email, hashed_password, is_active, is_superuser,
+                     ist_organisationsadmin, is_verified)
+                VALUES (%s, %s, %s, %s, %s, %s, %s, %s)
                 """,
                 (
                     user_id,
@@ -96,6 +106,7 @@ class UserDatabase(BaseUserDatabase[User, uuid.UUID]):
                     create_dict["hashed_password"],
                     create_dict.get("is_active", True),
                     create_dict.get("is_superuser", False),
+                    create_dict.get("ist_organisationsadmin", False),
                     create_dict.get("is_verified", True),
                 ),
             )
@@ -168,6 +179,50 @@ async def require_admin(user: User = Depends(get_current_user)) -> User:
     return user
 
 
+async def require_org_admin(user: User = Depends(get_current_user)) -> User:
+    """
+    Für Self-Service-Kontenverwaltung (/organisation/konten): erlaubt
+    entweder is_superuser (internes Tuxflotte-Personal, soll nicht
+    ausgesperrt sein, falls Support nötig ist) oder ist_organisationsadmin
+    (die neue, auf die eigene Organisation beschränkte Rolle). Bewusst kein
+    Ersatz für require_admin - is_superuser bleibt exklusiv für /admin/*.
+    """
+
+    if not (user.is_superuser or user.ist_organisationsadmin):
+        raise HTTPException(status_code=403, detail="Kein Admin-Zugriff für diese Organisation.")
+
+    return user
+
+
+def fetch_benutzer_fuer_organisation(organization_id: str) -> list[dict]:
+    """
+    Kontenliste einer Organisation - gemeinsam genutzt vom internen
+    Admin-Bereich (admin_kunden.py) und der Self-Service-Seite
+    (routers/organisation.py), um die SQL-Abfrage nicht zu duplizieren
+    (siehe ADR-0017 fetch_gruppen()-Reuse-Pattern).
+    """
+
+    with get_database_connection() as conn:
+        with conn.cursor() as cur:
+            cur.execute(
+                """
+                SELECT id, email, is_superuser, ist_organisationsadmin, created_at
+                FROM benutzer WHERE organization_id = %s ORDER BY email
+                """,
+                (organization_id,),
+            )
+            return [
+                {
+                    "id": str(benutzer_id),
+                    "email": email,
+                    "is_superuser": is_superuser,
+                    "ist_organisationsadmin": ist_organisationsadmin,
+                    "created_at": created_at,
+                }
+                for benutzer_id, email, is_superuser, ist_organisationsadmin, created_at in cur.fetchall()
+            ]
+
+
 router = APIRouter()
 
 
diff --git a/migrations/0005_organisationsadmin_rolle.sql b/migrations/0005_organisationsadmin_rolle.sql
new file mode 100644
index 0000000..01c40a7
--- /dev/null
+++ b/migrations/0005_organisationsadmin_rolle.sql
@@ -0,0 +1,11 @@
+BEGIN;
+
+-- Organisationsgebundene Admin-Rolle fuer Self-Service-Kontenverwaltung
+-- (/organisation/konten) - bewusst getrennt von is_superuser, das
+-- weiterhin ausschliesslich organisationsuebergreifendes, internes
+-- Tuxflotte-Personal mit Zugriff auf /admin/* bedeutet. Eine Kundin darf
+-- sich selbst nie is_superuser setzen koennen, nur dieses neue,
+-- auf die eigene Organisation beschraenkte Flag.
+ALTER TABLE benutzer ADD COLUMN ist_organisationsadmin BOOLEAN NOT NULL DEFAULT FALSE;
+
+COMMIT;
diff --git a/routers/admin_kunden.py b/routers/admin_kunden.py
index fba182d..d47706a 100644
--- a/routers/admin_kunden.py
+++ b/routers/admin_kunden.py
@@ -2,27 +2,13 @@ from fastapi import APIRouter, Depends, Form, HTTPException, Request
 from fastapi.responses import RedirectResponse
 
 from anode_client import anode_request
-from auth import UserCreate, UserManager, get_user_manager, require_admin
-from db import get_database_connection
+from auth import UserCreate, UserManager, fetch_benutzer_fuer_organisation, get_user_manager, require_admin
 from templating import templates
 
 
 router = APIRouter(prefix="/admin/kunden")
 
 
-def fetch_benutzer_fuer_organisation(organization_id: str) -> list[dict]:
-    with get_database_connection() as conn:
-        with conn.cursor() as cur:
-            cur.execute(
-                "SELECT email, is_superuser, created_at FROM benutzer WHERE organization_id = %s ORDER BY email",
-                (organization_id,),
-            )
-            return [
-                {"email": email, "is_superuser": is_superuser, "created_at": created_at}
-                for email, is_superuser, created_at in cur.fetchall()
-            ]
-
-
 @router.get("")
 def index(request: Request, user: dict = Depends(require_admin)):
     result = anode_request("GET", "/api/v1/organizations")
@@ -80,6 +66,33 @@ def detail(request: Request, organization_id: str, user: dict = Depends(require_
     )
 
 
+@router.post("/{organization_id}/organisationsdaten")
+def organisationsdaten_speichern(
+    organization_id: str,
+    name: str = Form(...),
+    kontakt_name: str = Form(default=""),
+    adresse: str = Form(default=""),
+    telefon: str = Form(default=""),
+    kontakt_email: str = Form(default=""),
+    notizen: str = Form(default=""),
+    user: dict = Depends(require_admin),
+):
+    anode_request(
+        "PATCH",
+        f"/api/v1/organizations/{organization_id}",
+        json={
+            "name": name,
+            "kontakt_name": kontakt_name or None,
+            "adresse": adresse or None,
+            "telefon": telefon or None,
+            "kontakt_email": kontakt_email or None,
+            "notizen": notizen or None,
+        },
+    )
+
+    return RedirectResponse(f"/admin/kunden/{organization_id}", status_code=303)
+
+
 @router.post("/{organization_id}/gruppen")
 def gruppe_anlegen(organization_id: str, name: str = Form(...), user: dict = Depends(require_admin)):
     anode_request("POST", f"/api/v1/organizations/{organization_id}/gruppen", json={"name": name})
@@ -215,6 +228,7 @@ async def konto_anlegen(
     email: str = Form(...),
     password: str = Form(...),
     is_superuser: str = Form(default=""),
+    ist_organisationsadmin: str = Form(default=""),
     user: dict = Depends(require_admin),
     user_manager: UserManager = Depends(get_user_manager),
 ):
@@ -224,6 +238,7 @@ async def konto_anlegen(
             password=password,
             organization_id=organization_id,
             is_superuser=is_superuser == "on",
+            ist_organisationsadmin=ist_organisationsadmin == "on",
         )
     )
 
diff --git a/routers/organisation.py b/routers/organisation.py
index 927c214..af3439b 100644
--- a/routers/organisation.py
+++ b/routers/organisation.py
@@ -2,7 +2,14 @@ from fastapi import APIRouter, Depends, Form, HTTPException, Request
 from fastapi.responses import RedirectResponse
 
 from anode_client import anode_request
-from auth import get_current_user
+from auth import (
+    UserCreate,
+    UserManager,
+    fetch_benutzer_fuer_organisation,
+    get_current_user,
+    get_user_manager,
+    require_org_admin,
+)
 from templating import templates
 
 
@@ -16,13 +23,85 @@ def organisation_ansicht(request: Request, user=Depends(get_current_user)):
     if not result.get("success"):
         raise HTTPException(status_code=404, detail="Organisation wurde nicht gefunden.")
 
+    benutzer = fetch_benutzer_fuer_organisation(str(user.organization_id))
+
     return templates.TemplateResponse(
-        request, "organisation.html", {"user": user, "organization": result["organization"]}
+        request,
+        "organisation.html",
+        {"user": user, "organization": result["organization"], "benutzer": benutzer},
     )
 
 
 @router.post("/organisation")
-def organisation_speichern(name: str = Form(...), user=Depends(get_current_user)):
-    anode_request("PATCH", f"/api/v1/organizations/{user.organization_id}", json={"name": name})
+def organisation_speichern(
+    name: str = Form(...),
+    kontakt_name: str = Form(default=""),
+    adresse: str = Form(default=""),
+    telefon: str = Form(default=""),
+    kontakt_email: str = Form(default=""),
+    notizen: str = Form(default=""),
+    user=Depends(get_current_user),
+):
+    anode_request(
+        "PATCH",
+        f"/api/v1/organizations/{user.organization_id}",
+        json={
+            "name": name,
+            "kontakt_name": kontakt_name or None,
+            "adresse": adresse or None,
+            "telefon": telefon or None,
+            "kontakt_email": kontakt_email or None,
+            "notizen": notizen or None,
+        },
+    )
+
+    return RedirectResponse("/organisation", status_code=303)
+
+
+@router.post("/organisation/konten")
+async def konto_anlegen(
+    email: str = Form(...),
+    password: str = Form(...),
+    ist_organisationsadmin: str = Form(default=""),
+    user=Depends(require_org_admin),
+    user_manager: UserManager = Depends(get_user_manager),
+):
+    # organization_id kommt bewusst nie aus dem Formular, sondern immer aus
+    # der Session des anfragenden Nutzers - verhindert, dass jemand per
+    # manipuliertem Request ein Konto in einer fremden Organisation anlegt.
+    # is_superuser wird beim Self-Service-Aufruf nie gesetzt (Default False)
+    # - das bleibt exklusiv dem internen Admin-Bereich vorbehalten (siehe
+    # ADR zu is_superuser vs. ist_organisationsadmin).
+    await user_manager.create(
+        UserCreate(
+            email=email,
+            password=password,
+            organization_id=user.organization_id,
+            ist_organisationsadmin=ist_organisationsadmin == "on",
+        )
+    )
+
+    return RedirectResponse("/organisation", status_code=303)
+
+
+@router.post("/organisation/konten/{konto_id}/loeschen")
+async def konto_loeschen(
+    konto_id: str,
+    user=Depends(require_org_admin),
+    user_manager: UserManager = Depends(get_user_manager),
+):
+    if str(user.id) == konto_id:
+        raise HTTPException(status_code=400, detail="Das eigene Konto kann nicht gelöscht werden.")
+
+    ziel = next(
+        (b for b in fetch_benutzer_fuer_organisation(str(user.organization_id)) if b["id"] == konto_id),
+        None,
+    )
+
+    if ziel is None:
+        raise HTTPException(status_code=404, detail="Konto wurde nicht gefunden.")
+
+    ziel_user = await user_manager.get_by_email(ziel["email"])
+    await user_manager.delete(ziel_user)
 
     return RedirectResponse("/organisation", status_code=303)
diff --git a/templates/admin/kunden_detail.html b/templates/admin/kunden_detail.html
index 0975775..ee8ee4c 100644
--- a/templates/admin/kunden_detail.html
+++ b/templates/admin/kunden_detail.html
@@ -4,6 +4,31 @@
 <p><a href="/admin/kunden">← Kunden</a></p>
 <h2>{{ organization.name if organization else organization_id }}</h2>
 
+<section>
+    <h3>Organisationsdaten</h3>
+    <form method="post" action="/admin/kunden/{{ organization_id }}/organisationsdaten">
+        <label for="org_name">Name</label>
+        <input type="text" id="org_name" name="name" value="{{ organization.name if organization else '' }}" required>
+
+        <label for="org_kontakt_name">Ansprechpartner:in</label>
+        <input type="text" id="org_kontakt_name" name="kontakt_name" value="{{ organization.kontakt_name or '' if organization else '' }}">
+
+        <label for="org_adresse">Adresse</label>
+        <input type="text" id="org_adresse" name="adresse" value="{{ organization.adresse or '' if organization else '' }}">
+
+        <label for="org_telefon">Telefon</label>
+        <input type="text" id="org_telefon" name="telefon" value="{{ organization.telefon or '' if organization else '' }}">
+
+        <label for="org_kontakt_email">Kontakt-E-Mail</label>
+        <input type="email" id="org_kontakt_email" name="kontakt_email" value="{{ organization.kontakt_email or '' if organization else '' }}">
+
+        <label for="org_notizen">Notizen</label>
+        <textarea id="org_notizen" name="notizen" rows="3">{{ organization.notizen or '' if organization else '' }}</textarea>
+
+        <button type="submit">Speichern</button>
+    </form>
+</section>
+
 <section>
     <h3>Aktivierungscodes</h3>
     <figure>
@@ -90,12 +115,13 @@
     <h3>Kundenkonten</h3>
     <figure>
     <table>
-        <thead><tr><th>E-Mail</th><th>Admin</th><th>Angelegt</th></tr></thead>
+        <thead><tr><th>E-Mail</th><th>Tuxflotte-Admin</th><th>Org-Admin</th><th>Angelegt</th></tr></thead>
         <tbody>
         {% for b in benutzer %}
             <tr>
                 <td>{{ b.email }}</td>
                 <td>{{ "ja" if b.is_superuser else "nein" }}</td>
+                <td>{{ "ja" if b.ist_organisationsadmin else "nein" }}</td>
                 <td>{{ b.created_at }}</td>
             </tr>
         {% endfor %}
@@ -111,7 +137,11 @@
         <input type="password" id="password" name="password" required>
         <label>
             <input type="checkbox" name="is_superuser">
-            Admin-Zugriff (organisationsübergreifend)
+            Admin-Zugriff (organisationsübergreifend, internes Tuxflotte-Personal)
+        </label>
+        <label>
+            <input type="checkbox" name="ist_organisationsadmin">
+            Admin dieser Organisation (darf eigene Kolleg:innen-Konten verwalten)
         </label>
         <button type="submit">Anlegen</button>
     </form>
diff --git a/templates/organisation.html b/templates/organisation.html
index 8ab6fd3..1ab50c4 100644
--- a/templates/organisation.html
+++ b/templates/organisation.html
@@ -6,6 +6,70 @@
 <form method="post" action="/organisation">
     <label for="name">Name</label>
     <input type="text" id="name" name="name" value="{{ organization.name }}" required>
+
+    <label for="kontakt_name">Ansprechpartner:in</label>
+    <input type="text" id="kontakt_name" name="kontakt_name" value="{{ organization.kontakt_name or '' }}">
+
+    <label for="adresse">Adresse</label>
+    <input type="text" id="adresse" name="adresse" value="{{ organization.adresse or '' }}">
+
+    <label for="telefon">Telefon</label>
+    <input type="text" id="telefon" name="telefon" value="{{ organization.telefon or '' }}">
+
+    <label for="kontakt_email">Kontakt-E-Mail</label>
+    <input type="email" id="kontakt_email" name="kontakt_email" value="{{ organization.kontakt_email or '' }}">
+
+    <label for="notizen">Notizen</label>
+    <textarea id="notizen" name="notizen" rows="3">{{ organization.notizen or '' }}</textarea>
+
     <button type="submit">Speichern</button>
 </form>
+
+<section>
+    <h3>Kolleg:innen</h3>
+    {% if not benutzer %}
+        <p>Keine Konten gefunden.</p>
+    {% else %}
+    <figure>
+    <table>
+        <thead><tr><th>E-Mail</th><th>Org-Admin</th><th>Angelegt</th>{% if user.is_superuser or user.ist_organisationsadmin %}<th></th>{% endif %}</tr></thead>
+        <tbody>
+        {% for b in benutzer %}
+            <tr>
+                <td>{{ b.email }}</td>
+                <td>{{ "ja" if b.ist_organisationsadmin else "nein" }}</td>
+                <td>{{ b.created_at }}</td>
+                {% if user.is_superuser or user.ist_organisationsadmin %}
+                <td>
+                    {% if b.id != user.id|string %}
+                    <form method="post" action="/organisation/konten/{{ b.id }}/loeschen">
+                        <button type="submit" class="outline secondary">Löschen</button>
+                    </form>
+                    {% endif %}
+                </td>
+                {% endif %}
+            </tr>
+        {% endfor %}
+        </tbody>
+    </table>
+    </figure>
+    {% endif %}
+
+    {% if user.is_superuser or user.ist_organisationsadmin %}
+    <details>
+    <summary role="button" class="secondary outline">Neues Konto anlegen</summary>
+    <form method="post" action="/organisation/konten">
+        <label for="konto_email">E-Mail</label>
+        <input type="email" id="konto_email" name="email" required>
+        <label for="konto_password">Passwort</label>
+        <input type="password" id="konto_password" name="password" required>
+        <label>
+            <input type="checkbox" name="ist_organisationsadmin">
+            Admin dieser Organisation (darf Kolleg:innen-Konten verwalten)
+        </label>
+        <button type="submit">Anlegen</button>
+    </form>
+    </details>
+    {% endif %}
+</section>
 {% endblock %}