diff --git a/docs/ProgrammersManual.html b/docs/ProgrammersManual.html
index 060bbb6d91b..3bec325d6ce 100644
--- a/docs/ProgrammersManual.html
+++ b/docs/ProgrammersManual.html
@@ -811,6 +811,10 @@ found at <a href="http://www.graphviz.org/doc/info/attrs.html">Graph
 Attributes</a>.)  If you want to restart and clear all the current graph
 attributes, then you can <tt>call DAG.clearGraphAttrs()</tt>. </p>
 
+<p>Note that graph visualization features are compiled out of Release builds
+to reduce file size.  This means that you need a Debug+Asserts or 
+Release+Asserts build to use these features.</p>
+
 </div>
 
 </div>