diff --git a/pymbolic/interop/sympy.py b/pymbolic/interop/sympy.py
index 6d7afc8744413ca3bc2a720f4f20465193313fd5..80fa435d98632766442c2b40be466620c31cfaa9 100644
--- a/pymbolic/interop/sympy.py
+++ b/pymbolic/interop/sympy.py
@@ -28,6 +28,7 @@ THE SOFTWARE.
 from pymbolic.interop.common import (
     SympyLikeToPymbolicMapper, PymbolicToSympyLikeMapper)
 
+import pymbolic.primitives as prim
 import sympy