diff --git a/setup.py b/setup.py
index f7c4cb6..8ebde99 100644
--- a/setup.py
+++ b/setup.py
@@ -44,7 +44,7 @@
 # Molecular Dynamics deps
 mddeps = [
     'MDAnalysis==2',
-    'mdtraj>=1,<2',
+    'mdtraj>=1.9,<2',
     ]
 
 alldeps = mddeps + supdeps