diff --git a/cookbook/service_container/scopes.rst b/cookbook/service_container/scopes.rst
index f305a97837d..f84a51a8704 100644
--- a/cookbook/service_container/scopes.rst
+++ b/cookbook/service_container/scopes.rst
@@ -216,6 +216,11 @@ your code. This should also be taken into account when declaring your service:
                 ->setSynthetic(true)
                 ->setSynchronized(true);
 
+.. caution::
+   
+   The service using the synchronized service will need to be public in order have its
+   setter called when the scope changes.
+
 .. _changing-service-scope:
 
 Changing the Scope of your Service