diff --git a/Cantera/cxx/include/Cantera.mak.in b/Cantera/cxx/include/Cantera.mak.in
index cb0cfec51..29d63639f 100644
--- a/Cantera/cxx/include/Cantera.mak.in
+++ b/Cantera/cxx/include/Cantera.mak.in
@@ -23,6 +23,8 @@
 #
 in_CanteraBuildTree = 0
 
+CANTERA_VERSION=@ctversion@
+
 ###############################################################################
 #        CANTERA CORE 
 ###############################################################################
@@ -122,6 +124,10 @@ endif
 #
 CANTERA_TOTAL_INCLUDES= $(CANTERA_CORE_INCLUDES) $(CANTERA_BOOST_INCLUDES) $(CANTERA_CVODE_INCLUDE)
 #
+# You can add this into the compilation environment to identify the version number
+#
+CANTERA_DEFINES = -DCANTERA_VERSION=@ctversion@
+#
 # LIBS and LIBS should be the same ...
 #
 CANTERA_TOTAL_LIBS2 =  -L$(CANTERA_LIBSDIR)  @LOCAL_LIBS@
diff --git a/Cantera/cxx/include/Cantera_bt.mak.in b/Cantera/cxx/include/Cantera_bt.mak.in
index f9566f2bf..b98df72c3 100644
--- a/Cantera/cxx/include/Cantera_bt.mak.in
+++ b/Cantera/cxx/include/Cantera_bt.mak.in
@@ -23,6 +23,8 @@
 #
 in_CanteraBuildTree = 0
 
+CANTERA_VERSION=@ctversion@
+
 ###############################################################################
 #        CANTERA CORE 
 ###############################################################################
@@ -117,6 +119,10 @@ endif
 ####################################################################
 
 CANTERA_TOTAL_INCLUDES= $(CANTERA_CORE_INCLUDES) $(CANTERA_BOOST_INCLUDES) $(CANTERA_CVODE_INCLUDE)
+#
+# You can add this into the compilation environment to identify the version number
+#
+CANTERA_DEFINES = -DCANTERA_VERSION=@ctversion@
 
 CANTERA_TOTAL_LIBS2 = @LOCAL_LIB_DIRS@ @LOCAL_LIBS@
 
diff --git a/preconfig b/preconfig
index ee7b62fea..7aa1de70e 100755
--- a/preconfig
+++ b/preconfig
@@ -488,8 +488,22 @@ CT_SHARED_LIB=${CT_SHARED_LIB:=clib}
 # lowercase 'helvetica'.
 RPFONT=${RPFONT:="Helvetica"}
 
-# Don't change this.
-CANTERA_VERSION=${CANTERA_VERSION:="1.8.0"} 
+#
+# Version Control:
+#
+#  We define a new string for every branch created in svn.
+#
+#        Currently expected versions:
+#         "1.7"                           Old version of Cantera
+#         "1.8.0"                         Released version of 1.8
+#         "1.8.x"                         Development version of 1.8
+#         "1.8_liquidTransportDevelop"    branched version of 1.8 having to deal with liquid transport
+#
+#    This field gets written into config.h  and is also an autoconf variable.
+#
+# 
+CANTERA_VERSION=${CANTERA_VERSION:="1.8.x"}
+
 
 #-----------------------------------------------------------------------
 #------------------- don't change anything below!! ---------------------