diff --git a/la_chariotte/order/models.py b/la_chariotte/order/models.py
index 7329c72..1bc8862 100644
--- a/la_chariotte/order/models.py
+++ b/la_chariotte/order/models.py
@@ -49,7 +49,9 @@ class GroupedOrder(models.Model):
 
     def clean_fields(self, exclude=None):
         super().clean_fields(exclude=exclude)
-        if self.delivery_date < timezone.now().date():
+        if self.delivery_date < timezone.now().date() and not self.pk:
+            # if the grouped order is being created (not updated), it cannot be in the past
+            # if we are updating, it's ok
             raise ValidationError("La date de livraison ne doit pas être dans le passé")
 
         if self.delivery_date < self.deadline.date():
diff --git a/la_chariotte/order/templates/order/grouped_order_overview.html b/la_chariotte/order/templates/order/grouped_order_overview.html
index b601140..1a78d96 100644
--- a/la_chariotte/order/templates/order/grouped_order_overview.html
+++ b/la_chariotte/order/templates/order/grouped_order_overview.html
@@ -31,9 +31,8 @@
           Livraison le {{ grouped_order.delivery_date }}
         </p>
         <div class="buttons">
-          <a class="button is-light" href={% url 'order:grouped_order_detail' grouped_order.id %}>
-            <i class="fa fa-eye mr-3" aria-hidden="true"></i>Page de la commande
-          </a>
+          <a class="button is-light" href="{% url 'order:update_grouped_order' grouped_order.id %}">
+            <i class="fa fa-pencil mr-3" aria-hidden="true"></i>Modifier la commande</a>
         </div>
       </div>
     </div>
diff --git a/la_chariotte/order/templates/order/grouped_order_update.html b/la_chariotte/order/templates/order/grouped_order_update.html
new file mode 100644
index 0000000..80da6d6
--- /dev/null
+++ b/la_chariotte/order/templates/order/grouped_order_update.html
@@ -0,0 +1,19 @@
+{% extends 'base.html' %}
+
+{% block title %}Modifier la commande groupée{% endblock %}
+
+{% block content %}
+<p class="desktop-hidden mobile-content-title">
+	{% block content_title %}Modifier la commande groupée{% endblock %}
+</p>
+<div class="box">
+    <p class="title">{{ grouped_order.name }} - modifier</p>
+    <form method="post">{% csrf_token %}
+        {{ form.as_p }}
+        <div class="buttons">
+            <a class="button is-light" href="{% url 'order:index' %}">Annuler</a>
+            <input class="button is-primary" type="submit" value="Suivant">
+        </div>
+    </form>
+</div>
+{% endblock %}
\ No newline at end of file
diff --git a/la_chariotte/order/tests/test_views.py b/la_chariotte/order/tests/test_views.py
index 4754898..6c9bdbb 100644
--- a/la_chariotte/order/tests/test_views.py
+++ b/la_chariotte/order/tests/test_views.py
@@ -960,6 +960,125 @@ class TestGroupedOrderCreateView:
         )
 
 
+class TestGroupedOrderUpdateView:
+    def test_update_grouped_order(self, client_log):
+        """
+        The grouped order orga updates a grouped order updates an incoming grouped order.
+        """
+        grouped_order = create_grouped_order(
+            days_before_delivery_date=5,
+            days_before_deadline=2,
+            name="gr order test",
+            orga_user=auth.get_user(client_log),
+        )
+        assert models.GroupedOrder.objects.count() == 1
+        assert models.GroupedOrder.objects.first().name == "gr order test"
+        assert models.GroupedOrder.objects.first().place == None
+
+        # get the update form
+        update_grouped_order_url = reverse(
+            "order:update_grouped_order", kwargs={"pk": grouped_order.pk}
+        )
+        response = client_log.get(update_grouped_order_url)
+        assert response.status_code == 200
+
+        # post the update form
+        date = timezone.now().date() + datetime.timedelta(days=42)
+        deadline = timezone.now() + datetime.timedelta(days=32)
+        response = client_log.post(
+            update_grouped_order_url,
+            {
+                "name": "titre test modifié",
+                "deadline": deadline,
+                "delivery_date": date,
+                "place": "quelque part",
+            },
+        )
+        assert response.status_code == 302
+        assert response.url.endswith("gerer-produits")
+        assert models.GroupedOrder.objects.count() == 1
+        assert models.GroupedOrder.objects.first().name == "titre test modifié"
+        assert models.GroupedOrder.objects.first().place == "quelque part"
+
+    def test_update_grouped_order__delivery_date_passed(self, client_log):
+        """
+        The grouped order orga updates a grouped order.
+        They can put an old delivery date.
+        """
+        grouped_order = create_grouped_order(
+            days_before_delivery_date=5,
+            days_before_deadline=2,
+            name="gr order test",
+            orga_user=auth.get_user(client_log),
+        )
+        assert models.GroupedOrder.objects.count() == 1
+        assert models.GroupedOrder.objects.first().name == "gr order test"
+        assert models.GroupedOrder.objects.first().place == None
+
+        # get the update form
+        update_grouped_order_url = reverse(
+            "order:update_grouped_order", kwargs={"pk": grouped_order.pk}
+        )
+        response = client_log.get(update_grouped_order_url)
+        assert response.status_code == 200
+
+        # post the update form
+        date = timezone.now().date() + datetime.timedelta(days=-1)
+        deadline = timezone.now() + datetime.timedelta(days=-3)
+        response = client_log.post(
+            update_grouped_order_url,
+            {
+                "name": "titre test modifié",
+                "deadline": deadline,
+                "delivery_date": date,
+                "place": "quelque part",
+            },
+        )
+        assert response.status_code == 302
+        assert response.url.endswith("gerer-produits")
+        assert models.GroupedOrder.objects.count() == 1
+        assert models.GroupedOrder.objects.first().name == "titre test modifié"
+        assert models.GroupedOrder.objects.first().place == "quelque part"
+
+    def test_update_grouped_order__not_orga(self, client_log, other_user):
+        """A user that is not organiszer of the GO accesses update page.
+        They get a 403 error"""
+        grouped_order = create_grouped_order(
+            days_before_delivery_date=5,
+            days_before_deadline=2,
+            name="gr order test",
+            orga_user=other_user,
+        )
+
+        # get the update form
+        update_grouped_order_url = reverse(
+            "order:update_grouped_order", kwargs={"pk": grouped_order.pk}
+        )
+        response = client_log.get(update_grouped_order_url)
+        assert response.status_code == 403
+
+    def test_update_grouped_order__anonymous(self, client, other_user):
+        """An anonymous user accesses the update_page.
+        They get redirected to login page"""
+        grouped_order = create_grouped_order(
+            days_before_delivery_date=5,
+            days_before_deadline=2,
+            name="gr order test",
+            orga_user=other_user,
+        )
+
+        # get the update form
+        update_grouped_order_url = reverse(
+            "order:update_grouped_order", kwargs={"pk": grouped_order.pk}
+        )
+        response = client.get(update_grouped_order_url)
+        assert response.status_code == 302
+        assert (
+            response.url
+            == f"{reverse('accounts:login')}?next={update_grouped_order_url}"
+        )
+
+
 class TestGroupedOrderAddItemsView:
     def test_get_manage_items__user_not_orga(self, client_log, other_user):
         """
@@ -1162,7 +1281,7 @@ class TestGroupedOrderSheetView:
         response = client_log.get(generate_sheet_url)
         assert response.status_code == 403
 
-    def test_get__not_orga(self, client, other_user):
+    def test_get__anonymous(self, client, other_user):
         """An anonymous user accesses the sheet view.
         They get redirected to login page"""
         grouped_order = create_grouped_order(
diff --git a/la_chariotte/order/urls.py b/la_chariotte/order/urls.py
index 2f06177..33dda0e 100644
--- a/la_chariotte/order/urls.py
+++ b/la_chariotte/order/urls.py
@@ -25,6 +25,11 @@ urlpatterns = [
         views.GroupedOrderAddItemsView.as_view(),
         name="manage_items",
     ),
+    path(
+        "<int:pk>/modifier",
+        views.GroupedOrderUpdateView.as_view(),
+        name="update_grouped_order",
+    ),
     path(
         "<int:pk>/gerer-produits/nouveau",
         views.ItemCreateView.as_view(),
diff --git a/la_chariotte/order/views.py b/la_chariotte/order/views.py
index 49a4f01..099f6ee 100644
--- a/la_chariotte/order/views.py
+++ b/la_chariotte/order/views.py
@@ -112,6 +112,19 @@ class GroupedOrderCreateView(LoginRequiredMixin, generic.CreateView):
         return kwargs
 
 
+class GroupedOrderUpdateView(UserPassesTestMixin, generic.UpdateView):
+    """View for updating a grouped order"""
+
+    model = GroupedOrder
+    template_name = "order/grouped_order_update.html"
+    fields = ["name", "deadline", "delivery_date", "place", "description"]
+    context_object_name = "grouped_order"
+
+    def test_func(self):
+        """Accessible only if the requesting user is the grouped order organizer"""
+        return self.get_object().orga == self.request.user
+
+
 class GroupedOrderAddItemsView(UserPassesTestMixin, generic.ListView):
     """After creating grouped order, view for adding items to it"""