diff --git a/cpmpy/expressions/globalfunctions.py b/cpmpy/expressions/globalfunctions.py
index f97615691..16c050ce8 100644
--- a/cpmpy/expressions/globalfunctions.py
+++ b/cpmpy/expressions/globalfunctions.py
@@ -57,6 +57,7 @@ def decompose_comparison(self):
         Maximum
         Element
         Count
+        Abs
 
 """
 import copy