diff --git a/new-registration-app/main.py b/new-registration-app/main.py
index 9852b33..23c94df 100644
--- a/new-registration-app/main.py
+++ b/new-registration-app/main.py
@@ -164,6 +164,7 @@ async def add_team_registration(request: Request, event_id: int, session: Sessio
     statement = select(TeamRegistration).where(
         TeamRegistration.person_name == person, TeamRegistration.work_type == work_type
     )
+    # if the person has already registered for the same work type, just ignore
     if session.exec(statement).one_or_none() is None:
         registration = TeamRegistration(
             person_name=person,
diff --git a/new-registration-app/models.py b/new-registration-app/models.py
index 27c5927..8efc803 100644
--- a/new-registration-app/models.py
+++ b/new-registration-app/models.py
@@ -1,8 +1,10 @@
+import typing
 from datetime import datetime
-from typing import Literal
 
 from sqlmodel import Field, Relationship, SQLModel, String
 
+WorkTypes = typing.Literal["cooking", "dishes", "tables"]
+
 
 class Event(SQLModel, table=True):
     id: int | None = Field(default=None, primary_key=True)
@@ -19,20 +21,45 @@ class Event(SQLModel, table=True):
     team_dishes_min: int = 3
     team_dishes_max: int = 5
 
+    # Todo: Rename to "table"
     team_prep_min: int = 1
     team_prep_max: int = 1
 
     registrations: list["Registration"] = Relationship()
     team: list["TeamRegistration"] = Relationship()
 
+    def team_min_reached(self, work_type: WorkTypes):
+        threshold = {
+            "cooking": self.team_cooking_min,
+            "dishes": self.team_dishes_min,
+            "tables": self.team_prep_min,
+        }[work_type]
+        return sum(1 for t in self.team if t.work_type == work_type) >= threshold
+
+    def team_max_reached(self, work_type: WorkTypes):
+        threshold = {
+            "cooking": self.team_cooking_max,
+            "dishes": self.team_dishes_max,
+            "tables": self.team_prep_max,
+        }[work_type]
+        return sum(1 for t in self.team if t.work_type == work_type) >= threshold
+
+    def all_teams_min(self):
+        return all(
+            self.team_min_reached(work_type) for work_type in typing.get_args(WorkTypes)
+        )
+
+    def all_teams_max(self):
+        return all(
+            self.team_max_reached(work_type) for work_type in typing.get_args(WorkTypes)
+        )
+
 
 class TeamRegistration(SQLModel, table=True):
     id: int | None = Field(default=None, primary_key=True)
     event_id: int | None = Field(default=None, foreign_key="event.id")
     person_name: str = Field(nullable=False)
-    work_type: Literal["cooking", "dishes", "tables"] = Field(
-        nullable=False, sa_type=String
-    )
+    work_type: WorkTypes = Field(nullable=False, sa_type=String)
     comment: str | None
 
 
diff --git a/new-registration-app/templates/event.html b/new-registration-app/templates/event.html
index cb03742..4714ddf 100644
--- a/new-registration-app/templates/event.html
+++ b/new-registration-app/templates/event.html
@@ -24,7 +24,7 @@
             <button type="button" class="btn btn-primary mb-2" data-bs-toggle="modal" data-bs-target="#registration">
                 Anmeldung hinzufügen
             </button>
-            <button type="button" class="btn btn-primary mb-2" data-bs-toggle="modal" data-bs-target="#teamRegistration">
+            <button type="button" class="btn btn-primary mb-2 {% if event.all_teams_max() %}disabled{% endif %}" data-bs-toggle="modal" data-bs-target="#teamRegistration">
                 Dienst übernehmen
             </button>
             {% if event.recipe_link %}
@@ -41,7 +41,7 @@
                     <h5 class="card-title">Dienste</h5>
                     <div class="row">
                         <div class="col-md-4">
-                            Kochen: {% if event.team | selectattr("work_type", "equalto", "cooking") | list | count >= 3 %}✅{% endif %}
+                            Kochen: {% if event.team_min_reached("cooking") %}✅{% endif %}
                         </div>
                         <div class="col-md-8">
                             {{ teamEntries(event, "cooking") }}
@@ -50,7 +50,7 @@
                     <hr/>
                     <div class="row">
                         <div class="col-md-4">
-                            Spülen: {% if event.team | selectattr("work_type", "equalto", "dishes") | list | count >= 3 %}✅{% endif %}
+                            Spülen: {% if event.team_min_reached("dishes") %}✅{% endif %}
                         </div>
                         <div class="col-md-8">
                             {{ teamEntries(event, "dishes") }}
@@ -59,7 +59,7 @@
                     <hr/>
                     <div class="row">
                         <div class="col-md-4">
-                            Tische vorbereiten: {% if event.team | selectattr("work_type", "equalto", "tables") | list | count >= 1 %}✅{% endif %}
+                            Tische vorbereiten: {% if event.team_min_reached("tables") %}✅{% endif %}
                         </div>
                         <div class="col-md-8">
                             {{ teamEntries(event, "tables") }}
@@ -188,9 +188,9 @@
                         <div class="col-md-6">
                             <label for="workType" class="form-label">Dienst-Art</label>
                             <select id="workType" name="workType" class="form-select" aria-label="Multiple select example">
-                                <option value="cooking">Kochen</option>
-                                <option value="dishes">Spülen</option>
-                                <option value="tables">Tische vorbereiten</option>
+                                {% if not event.team_max_reached("cooking") %}<option value="cooking">Kochen</option>{% endif %}
+                                {% if not event.team_max_reached("dishes") %}<option value="dishes">Spülen</option>{% endif %}
+                                {% if not event.team_max_reached("tables") %}<option value="tables">Tische vorbereiten</option>{% endif %}
                             </select>
                         </div>
                     </div>