diff --git a/python/kwiver/sprokit/adapters/embedded_pipeline.cxx b/python/kwiver/sprokit/adapters/embedded_pipeline.cxx
index 9d46f05940..055129daa6 100644
--- a/python/kwiver/sprokit/adapters/embedded_pipeline.cxx
+++ b/python/kwiver/sprokit/adapters/embedded_pipeline.cxx
@@ -55,17 +55,26 @@ PYBIND11_MODULE(embedded_pipeline, m)
         ksp::embedded_pipeline_trampoline> ep(m, "EmbeddedPipeline");
   ep.def(init<>())
   .def("build_pipeline", &ksp::build_pipeline,
+    call_guard<kwiver::vital::python::gil_scoped_release>(),
     arg("desc_file"),
     arg("def_dir") = "")
-  .def("send", &kwiver::embedded_pipeline::send)
-  .def("send_end_of_input", &kwiver::embedded_pipeline::send_end_of_input)
-  .def("receive", &kwiver::embedded_pipeline::receive)
-  .def("full", &kwiver::embedded_pipeline::full)
-  .def("empty", &kwiver::embedded_pipeline::empty)
+  .def("send", &kwiver::embedded_pipeline::send,
+    call_guard<kwiver::vital::python::gil_scoped_release>())
+  .def("send_end_of_input", &kwiver::embedded_pipeline::send_end_of_input,
+    call_guard<kwiver::vital::python::gil_scoped_release>())
+  .def("receive", &kwiver::embedded_pipeline::receive,
+    call_guard<kwiver::vital::python::gil_scoped_release>())
+  .def("full", &kwiver::embedded_pipeline::full,
+    call_guard<kwiver::vital::python::gil_scoped_release>())
+  .def("empty", &kwiver::embedded_pipeline::empty,
+    call_guard<kwiver::vital::python::gil_scoped_release>())
   .def("at_end", &kwiver::embedded_pipeline::at_end)
-  .def("start", &kwiver::embedded_pipeline::start)
-  .def("wait", &kwiver::embedded_pipeline::wait)
-  .def("stop", &kwiver::embedded_pipeline::stop)
+  .def("start", &kwiver::embedded_pipeline::start,
+    call_guard<kwiver::vital::python::gil_scoped_release>())
+  .def("wait", &kwiver::embedded_pipeline::wait,
+    call_guard<kwiver::vital::python::gil_scoped_release>())
+  .def("stop", &kwiver::embedded_pipeline::stop,
+    call_guard<kwiver::vital::python::gil_scoped_release>())
   .def("input_port_names", &kwiver::embedded_pipeline::input_port_names)
   .def("output_port_names", &kwiver::embedded_pipeline::output_port_names)
   .def("input_adapter_connected",
@@ -73,11 +82,14 @@ PYBIND11_MODULE(embedded_pipeline, m)
   .def("output_adapter_connected",
       &ksp::wrap_embedded_pipeline::output_adapter_connected)
   .def("connect_input_adapter",
-      static_cast<bool (kwiver::embedded_pipeline::*)()>(&ksp::wrap_embedded_pipeline::connect_input_adapter))
+      static_cast<bool (kwiver::embedded_pipeline::*)()>(&ksp::wrap_embedded_pipeline::connect_input_adapter),
+      call_guard<kwiver::vital::python::gil_scoped_release>())
   .def("connect_output_adapter",
-      static_cast<bool (kwiver::embedded_pipeline::*)()>(&ksp::wrap_embedded_pipeline::connect_output_adapter))
+      static_cast<bool (kwiver::embedded_pipeline::*)()>(&ksp::wrap_embedded_pipeline::connect_output_adapter),
+      call_guard<kwiver::vital::python::gil_scoped_release>())
   .def("update_config",
-      static_cast<void (kwiver::embedded_pipeline::*)(kwiver::vital::config_block_sptr)>(&ksp::wrap_embedded_pipeline::update_config))
+      static_cast<void (kwiver::embedded_pipeline::*)(kwiver::vital::config_block_sptr)>(&ksp::wrap_embedded_pipeline::update_config),
+      call_guard<kwiver::vital::python::gil_scoped_release>())
   ;
   ep.doc() = R"(
         Python bindings for kwiver::embedded_pipeline
diff --git a/python/kwiver/vital/modules/module_helpers.cxx b/python/kwiver/vital/modules/module_helpers.cxx
index 08f4364ffd..61d42be578 100644
--- a/python/kwiver/vital/modules/module_helpers.cxx
+++ b/python/kwiver/vital/modules/module_helpers.cxx
@@ -28,6 +28,8 @@ namespace py = pybind11;
  */
 void check_and_initialize_python_interpretor()
 {
+  static bool initialized = false;
+
   // Check if a python interpreter already exists so we don't clobber sys.argv
   // (e.g. if sprokit is initialized from python)
   if (!Py_IsInitialized())
@@ -38,16 +40,20 @@ void check_and_initialize_python_interpretor()
     // Set Python interpeter attribute: sys.argv = []
     // parameters are: (argc, argv, updatepath)
     PySys_SetArgvEx(0, NULL, 0);
-  }
 
-  if (!PyEval_ThreadsInitialized())
-  {
+    // In Python 3.7+, threads are always initialized after Py_Initialize(),
+    // so PyEval_ThreadsInitialized() always returns true. We need to
+    // initialize pybind11 internals and release the GIL ourselves.
+    if (!initialized)
     {
-      // Let pybind11 initialize threads and set up its internal data structures
-      pybind11::detail::get_internals();
+      initialized = true;
+      {
+        // Let pybind11 initialize threads and set up its internal data structures
+        pybind11::detail::get_internals();
+      }
+      // Release the GIL so other threads can acquire it
+      PyEval_SaveThread();
     }
-    // Release the GIL
-    PyEval_SaveThread();
   }
 }