diff --git a/SpiffWorkflow/spiff/specs/service_task.py b/SpiffWorkflow/spiff/specs/service_task.py
index b1c63a943..80e3f3453 100644
--- a/SpiffWorkflow/spiff/specs/service_task.py
+++ b/SpiffWorkflow/spiff/specs/service_task.py
@@ -1,3 +1,4 @@
+from copy import deepcopy
 import json
 from SpiffWorkflow.bpmn.specs.ServiceTask import ServiceTask
 from SpiffWorkflow.spiff.specs.spiff_task import SpiffBpmnTask
@@ -27,7 +28,8 @@ class ServiceTask(SpiffBpmnTask, ServiceTask):
             param['value'] = task.workflow.script_engine.evaluate(task, param['value'])
             return param
 
-        evaluated_params = {k: evaluate(v) for k, v in self.operation_params.items()}
+        operation_params_copy = deepcopy(self.operation_params)
+        evaluated_params = {k: evaluate(v) for k, v in operation_params_copy.items()}
 
         result = task.workflow.script_engine.call_service(self.operation_name,
                 evaluated_params, task.data)
diff --git a/tests/SpiffWorkflow/spiff/ServiceTaskTest.py b/tests/SpiffWorkflow/spiff/ServiceTaskTest.py
index 9417b42ed..1d3035b3f 100644
--- a/tests/SpiffWorkflow/spiff/ServiceTaskTest.py
+++ b/tests/SpiffWorkflow/spiff/ServiceTaskTest.py
@@ -60,6 +60,15 @@ class ServiceTaskTest(BaseTestCase):
         self.workflow.do_engine_steps()
         self._assert_service_tasks()
 
+    def testRunSameServiceTaskActivityMultipleTimes(self):
+        self.workflow.do_engine_steps()
+        service_task_activity = [t for t in self.workflow.get_tasks() if
+                                 t.task_spec.name == 'Activity-1inxqgx'][0]
+
+        service_task_activity.task_spec._execute(service_task_activity)
+        service_task_activity.task_spec._execute(service_task_activity)
+        service_task_activity.task_spec._execute(service_task_activity)
+
     def testRunThroughSaveRestore(self):
         self.save_restore()
         # Engine isn't preserved through save/restore, so we have to reset it.