diff --git a/include/etl/version.h b/include/etl/version.h
index 166bccae..e3f0b39d 100644
--- a/include/etl/version.h
+++ b/include/etl/version.h
@@ -38,8 +38,8 @@ SOFTWARE.
 ///\ingroup utilities
 
 #define ETL_VERSION_MAJOR 20
-#define ETL_VERSION_MINOR  4
-#define ETL_VERSION_PATCH  1
+#define ETL_VERSION_MINOR  5
+#define ETL_VERSION_PATCH  0
 #define ETL_VERSION       ETL_STRINGIFY(ETL_VERSION_MAJOR) "." ETL_STRINGIFY(ETL_VERSION_MINOR) "." ETL_STRINGIFY(ETL_VERSION_PATCH)
 #define ETL_VERSION_W     ETL_STRINGIFY(ETL_VERSION_MAJOR) L"." ETL_STRINGIFY(ETL_VERSION_MINOR) L"." ETL_STRINGIFY(ETL_VERSION_PATCH)
 #define ETL_VERSION_U16   ETL_STRINGIFY(ETL_VERSION_MAJOR) u"." ETL_STRINGIFY(ETL_VERSION_MINOR) u"." ETL_STRINGIFY(ETL_VERSION_PATCH)
diff --git a/library.json b/library.json
index 76fa0807..4df8e9f7 100644
--- a/library.json
+++ b/library.json
@@ -1,6 +1,6 @@
 {
   "name": "ETL Embedded Template Library",
-  "version": "20.4.1",
+  "version": "20.5.0",
   "author s": {
     "name": "John Wellbelove",
     "email": "john.wellbelove@etlcpp.com"
diff --git a/library.properties b/library.properties
index 2fac9d6d..5b1e49c5 100644
--- a/library.properties
+++ b/library.properties
@@ -1,5 +1,5 @@
 name=Embedded Template Library ETL
-version=20.4.1
+version=20.5.0
 author= John Wellbelove <john.wellbelove@etlcpp.com>
 maintainer=John Wellbelove <john.wellbelove@etlcpp.com>
 license=MIT
diff --git a/support/Release notes.txt b/support/Release notes.txt
index 600da43c..865f157d 100644
--- a/support/Release notes.txt	
+++ b/support/Release notes.txt	
@@ -1,3 +1,10 @@
+===============================================================================
+20.5.0
+Added specialisation of etl::state_chart to allow a parameter to be passed along
+with the event.
+Issue #339 - Fix extent type conversion warning
+Issue #340 - Export headers as system includes
+
 ===============================================================================
 20.4.1
 Updates to etl::shared_message example application.