diff --git a/prism/CHANGELOG.txt b/prism/CHANGELOG.txt
index ed767904..1f5727de 100644
--- a/prism/CHANGELOG.txt
+++ b/prism/CHANGELOG.txt
@@ -5,17 +5,21 @@ of the main changes in each public release, see the file VERSIONS.txt.
 Latest changes (mostly reverse chronological):
 [correct wrt svn rev 3263]
 
-* Added if-and-only-if operator (<=>) for use in models/properties
-* Updated version of explicit model checking library
-* Testing mode (-test and -testall switches)
-* Various bug fixes
-
 Ongoing changes:
 
 * Properties can be named, by prefixing with "name":, and reference each other
 * More improvements to explicit engine
 * CTL AG/EF
 
+-----------------------------------------------------------------------------
+Version 4.0.1 (released ...)
+-----------------------------------------------------------------------------
+
+* Added if-and-only-if operator (<=>) for use in models/properties
+* Updated version of explicit model checking library
+* Testing mode (-test and -testall switches)
+* Various bug fixes
+
 -----------------------------------------------------------------------------
 Version 4.0 (released 28/6/2011)
 -----------------------------------------------------------------------------
diff --git a/prism/VERSIONS.txt b/prism/VERSIONS.txt
index 7465463d..e9643713 100644
--- a/prism/VERSIONS.txt
+++ b/prism/VERSIONS.txt
@@ -1,6 +1,15 @@
 This file summarises the principal changes between each main public release of PRISM.
 For more detailed information about the various changes, see the file CHANGELOG.txt.
 
+-----------------------------------------------------------------------------
+Version 4.0.1 (released ...)
+-----------------------------------------------------------------------------
+
+* Added if-and-only-if operator (<=>) for use in models/properties
+* Updated version of explicit model checking library
+* Testing mode (-test and -testall switches)
+* Various bug fixes
+
 -----------------------------------------------------------------------------
 Version 4.0 (beta released 16/12/2010)
 -----------------------------------------------------------------------------