diff --git a/configure.ac b/configure.ac
index 866e18e8ca..c599a1e758 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,6 +1,6 @@
 dnl Process with autoconf to generate configure script   -*- sh -*-
 
-AC_INIT(LyX,2.2.0,[lyx-devel@lists.lyx.org],[lyx])
+AC_INIT(LyX,2.2.1dev,[lyx-devel@lists.lyx.org],[lyx])
 AC_PRESERVE_HELP_ORDER
 # Use ISO format only. The frontend needs to parse this
 AC_SUBST(LYX_DATE, ["2016-05-23"])