diff --git a/NEWS.md b/NEWS.md
index ea22c5767..529fa2f38 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,5 +1,13 @@
 ## MLKit NEWS
 
+### MLKit version 4.6.1 is released
+
+* mael 2022-01-20: Make use of better finite map structures (based on
+  AVL trees) for all compiler and elaboration environments.
+
+* mael 2022-01-20: Faster serialisation of compiler bases by adopting
+  a non-sharing strategy in case there are many hash-collisions.
+
 * mael 2022-01-18: The maximum size of a string is now 4Gb (previously
   16Mb). For the JavaScript backend, the maximum size is now 1Gb
   (previously 16Mb). Same for Word8Vector.vector, CharArray.array, and
diff --git a/configure.ac b/configure.ac
index 9038fa2b5..a71eabec9 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,4 +1,4 @@
-AC_INIT(MLKit, [v4.6.0])
+AC_INIT(MLKit, [v4.6.1])
 AC_CONFIG_HEADERS([src/config.h])
 AC_REVISION($Revision$)
 AC_CONFIG_FILES([src/Runtime/Makefile