diff --git a/doc/misc/cl.texi b/doc/misc/cl.texi
index 98898b9eec0..079f534168c 100644
--- a/doc/misc/cl.texi
+++ b/doc/misc/cl.texi
@@ -77,6 +77,7 @@ Appendices
 Indexes
 * Function Index::                 An entry for each documented function.
 * Variable Index::                 An entry for each documented variable.
+* Concept Index::                  An entry for each concept.
 @end menu
 
 @node Overview