diff --git a/doc/lispintro/ChangeLog b/doc/lispintro/ChangeLog
index da5c9f671b5..6eb7604b05a 100644
--- a/doc/lispintro/ChangeLog
+++ b/doc/lispintro/ChangeLog
@@ -1,3 +1,7 @@
+2009-02-22  Karl Berry  <karl@gnu.org>
+
+	* emacs-lisp-intro.texi (Default Configuration): fix dup word "by by".
+
 2009-02-20  Juanma Barranquero  <lekktu@gmail.com>
 
 	* emacs-lisp-intro.texi (current-kill, Code for current-kill)
diff --git a/doc/lispintro/emacs-lisp-intro.texi b/doc/lispintro/emacs-lisp-intro.texi
index c3ba966895f..7c53d90d4c3 100644
--- a/doc/lispintro/emacs-lisp-intro.texi
+++ b/doc/lispintro/emacs-lisp-intro.texi
@@ -17009,7 +17009,7 @@ person hopes to do with an unadorned file?  Fundamental mode is the
 right default for such a file, just as C mode is the right default for
 editing C code.  (Enough programming languages have syntaxes
 that enable them to share or nearly share features, so C mode is
-now provided by by CC mode, the `C Collection'.)
+now provided by CC mode, the `C Collection'.)
 
 But when you do know who is going to use Emacs---you,
 yourself---then it makes sense to customize Emacs.