diff --git a/RIGS/rigboard.py b/RIGS/rigboard.py
index dbe7e6c7..e9597ab5 100644
--- a/RIGS/rigboard.py
+++ b/RIGS/rigboard.py
@@ -118,6 +118,14 @@ class EventUpdate(generic.UpdateView):
             value = form[field].value()
             if value is not None and value != '':
                 context[field] = model.objects.get(pk=value)
+
+        # If this event has already been emailed to a client, show a warning
+        if self.object.auth_request_at is not None:
+            messages.info(self.request, 'This event has already been sent to the client for authorisation, any changes you make will be visible to them immediately.')
+
+        if hasattr(self.object, 'authorised'):
+            messages.warning(self.request, 'This event has already been authorised by client, any changes to price will require reauthorisation.')
+
         return context
 
     def get_success_url(self):