diff --git a/modules/mol/mm/pymod/export_topology.cc b/modules/mol/mm/pymod/export_topology.cc
index bd0defb9a72d7c6bf60259a231db03eb12fa3a85..e95deb1ee812b33016c647851189593ed0b0c477 100644
--- a/modules/mol/mm/pymod/export_topology.cc
+++ b/modules/mol/mm/pymod/export_topology.cc
@@ -335,6 +335,7 @@ void export_Topology()
     .def("ResetExclusions",&ost::mol::mm::Topology::ResetExclusions)
     .def("AddHarmonicPositionRestraint",&ost::mol::mm::Topology::AddHarmonicPositionRestraint,(arg("index"),arg("ref_position"),arg("k"),arg("x_scale")=1.0,arg("y_scale")=1.0,arg("z_scale")=1.0))
     .def("AddHarmonicDistanceRestraint",&ost::mol::mm::Topology::AddHarmonicDistanceRestraint)
+    .def("Merge",&ost::mol::mm::Topology::Merge)
     //single atom parameter getter and setter functions
     .def("SetSigmas",&WrapSetSigmas)
     .def("SetSigma",&ost::mol::mm::Topology::SetSigma)