diff --git a/Documentation/guides/application-developer.rst b/Documentation/guides/application-developer.rst
index 1b2d7727..26d5fc1d 100644
--- a/Documentation/guides/application-developer.rst
+++ b/Documentation/guides/application-developer.rst
@@ -490,6 +490,10 @@ device:
    request->reuse(Request::ReuseBuffers);
    camera->queueRequest(request);
 
+Note that a request should only be marked for re-use if and only if the request
+will be re-queued to the camera device. Marking a request for re-use and not
+queuing it causes undefined behavior.
+
 Request queueing
 ----------------