diff --git a/ChangeLog b/ChangeLog
index 113b2f6..b873ec3 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,7 +1,7 @@
-2015-05-20  Juergen Knoedlseder  <jurgen.knodlseder@irap.omp.eu>
+2015-05-22  Juergen Knoedlseder  <jurgen.knodlseder@irap.omp.eu>
 
-        * Version 1.0.0 released
-        ========================
+        * Version 0.10.0 released
+        =========================
 
         Add optional PHASE information to CTA event lists
         Use URL path informtion in GVOClient connection to Hub
diff --git a/NEWS b/NEWS
index 9e082cb..8bfe95f 100644
--- a/NEWS
+++ b/NEWS
@@ -1,8 +1,8 @@
-New Features and Important Changes in GammaLib 1.0.0
+New Features and Important Changes in GammaLib 0.10.0
 
 Author(s) : Juergen Knoedlseder
 
-20 May 2015
+22 May 2015
 
 
 1. Introduction
diff --git a/configure.ac b/configure.ac
index 739a0f7..28c843e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -29,7 +29,7 @@
 #############################################################################
 # Initialisation                                                            #
 #############################################################################
-AC_INIT([gammalib], [1.0.0], [jurgen.knodlseder@irap.omp.eu], [gammalib])
+AC_INIT([gammalib], [0.10.0], [jurgen.knodlseder@irap.omp.eu], [gammalib])
 AC_CONFIG_SRCDIR([src/support/GTools.cpp])
 AC_CONFIG_MACRO_DIR([m4])
 AM_INIT_AUTOMAKE([gnu no-dependencies -Wno-portability subdir-objects])
diff --git a/doc/Doxyfile b/doc/Doxyfile
index 7b4e713..12dae5e 100644
--- a/doc/Doxyfile
+++ b/doc/Doxyfile
@@ -32,7 +32,7 @@ PROJECT_NAME           = GammaLib
 # This could be handy for archiving the generated documentation or
 # if some version control system is used.
 
-PROJECT_NUMBER         = 1.0.0
+PROJECT_NUMBER         = 0.10.0
 
 # Using the PROJECT_BRIEF tag one can provide an optional one line description
 # for a project that appears at the top of each page and should give viewer
diff --git a/doc/source/conf.py b/doc/source/conf.py
index 2d9b528..1d2c510 100644
--- a/doc/source/conf.py
+++ b/doc/source/conf.py
@@ -55,9 +55,9 @@ copyright = u'2006-2015, GammaLib developers'
 # built documents.
 #
 # The short X.Y version.
-version = '1.0'
+version = '0.10'
 # The full version, including alpha/beta/rc tags.
-release = '1.0.0'
+release = '0.10.0'
 
 # The language for content autogenerated by Sphinx. Refer to documentation
 # for a list of supported languages.
diff --git a/gammalib.pc.in b/gammalib.pc.in
index a061a04..cb784ea 100644
--- a/gammalib.pc.in
+++ b/gammalib.pc.in
@@ -6,7 +6,7 @@ includedir=${prefix}/include
 Name: GammaLib
 Description: Versatile toolbox for analysis of astronomical gamma-ray data
 URL: http://gammalib.sourceforge.net/
-Version: 1.0.0
+Version: 0.10.0
 Requires: 
 Requires.private: @CFITSIO@
 Conflicts: