diff --git a/doc/emacs/mule.texi b/doc/emacs/mule.texi
index 80b1384..e92aad1 100644
--- a/doc/emacs/mule.texi
+++ b/doc/emacs/mule.texi
@@ -1370,6 +1370,11 @@ display that character properly.  It will display that character as a
 hex code or thin space or an empty box instead.  (@xref{Text Display, ,
 glyphless characters}, for details.)
 
+@findex describe-fontset
+  @kbd{M-x describe-fontset} lists the complete range of characters
+and fonts assigned to them in a given fontset.  Its default is the
+fontset used by the current frame.
+
 @node Defining Fontsets
 @section Defining fontsets