diff --git a/mistral/engine1/policies.py b/mistral/engine1/policies.py
index af0257db..c290831a 100644
--- a/mistral/engine1/policies.py
+++ b/mistral/engine1/policies.py
@@ -24,6 +24,7 @@ from mistral.workflow import utils
 
 
 _ENGINE_CLIENT_PATH = 'mistral.engine1.rpc.get_engine_client'
+_RUN_TASK_EXECUTION_PATH = 'mistral.engine1.task_handler.run_task_execution'
 
 
 def _log_task_delay(task_ex, delay_sec):
@@ -156,10 +157,6 @@ class WaitBeforePolicy(base.TaskPolicy):
     def before_task_start(self, task_ex, task_spec):
         super(WaitBeforePolicy, self).before_task_start(task_ex, task_spec)
 
-        # TODO(rakhmerov): This policy needs to be fixed.
-        if True:
-            return
-
         context_key = 'wait_before_policy'
 
         runtime_context = _ensure_context_has_key(
@@ -190,10 +187,10 @@ class WaitBeforePolicy(base.TaskPolicy):
         task_ex.state = states.DELAYED
 
         scheduler.schedule_call(
-            _ENGINE_CLIENT_PATH,
-            'run_task',
+            None,
+            _RUN_TASK_EXECUTION_PATH,
             self.delay,
-            task_id=task_ex.id
+            task_ex_id=task_ex.id,
         )
 
 
diff --git a/mistral/engine1/task_handler.py b/mistral/engine1/task_handler.py
index a415753d..2fca4c27 100644
--- a/mistral/engine1/task_handler.py
+++ b/mistral/engine1/task_handler.py
@@ -36,6 +36,31 @@ from mistral.workflow import with_items
 LOG = logging.getLogger(__name__)
 
 
+def run_task_execution(task_ex_id):
+    """This function runs existent task execution.
+
+    It is needed mostly by scheduler.
+    """
+    task_ex = db_api.get_task_execution(task_ex_id)
+    task_spec = spec_parser.get_task_spec(task_ex.spec)
+    wf_spec = spec_parser.get_workflow_spec(
+        db_api.get_workflow_definition(task_ex.workflow_name).spec
+    )
+
+    # Explicitly change task state to RUNNING.
+    task_ex.state = states.RUNNING
+
+    _run_task_execution(task_ex, task_spec, wf_spec)
+
+
+def _run_task_execution(task_ex, task_spec, wf_spec):
+    input_dicts = _get_input_dictionaries(
+        wf_spec, task_ex, task_spec, task_ex.in_context
+    )
+    for input_d in input_dicts:
+        _run_action_or_workflow(task_ex, task_spec, input_d)
+
+
 def run_task(wf_cmd):
     """Runs a task."""
     ctx = wf_cmd.ctx
@@ -59,8 +84,7 @@ def run_task(wf_cmd):
     if task_ex.state != states.RUNNING:
         return
 
-    for input_d in _get_input_dictionaries(wf_spec, task_ex, task_spec, ctx):
-        _run_action_or_workflow(task_ex, task_spec, input_d)
+    _run_task_execution(task_ex, task_spec, wf_spec)
 
 
 def on_action_complete(action_ex, result):
diff --git a/mistral/tests/unit/engine1/test_policies.py b/mistral/tests/unit/engine1/test_policies.py
index 850da283..e660549b 100644
--- a/mistral/tests/unit/engine1/test_policies.py
+++ b/mistral/tests/unit/engine1/test_policies.py
@@ -253,7 +253,6 @@ class PoliciesTest(base.EngineTestCase):
         thread_group = scheduler.setup()
         self.addCleanup(thread_group.stop)
 
-    @testtools.skip("Fix policies.")
     def test_build_policies(self):
         arr = policies.build_policies(
             self.task_spec.get_policies(),
@@ -329,7 +328,6 @@ class PoliciesTest(base.EngineTestCase):
 
         self.assertIsInstance(p, policies.TimeoutPolicy)
 
-    @testtools.skip("Fix 'wait-before' policy.")
     def test_wait_before_policy(self):
         wb_service.create_workbook_v2(WAIT_BEFORE_WB)
 
@@ -348,7 +346,6 @@ class PoliciesTest(base.EngineTestCase):
 
         self._await(lambda: self.is_execution_success(wf_ex.id))
 
-    @testtools.skip("Fix 'wait-before' policy.")
     def test_wait_before_policy_from_var(self):
         wb_service.create_workbook_v2(WAIT_BEFORE_FROM_VAR)
 
diff --git a/mistral/utils/serializer.py b/mistral/utils/serializers.py
similarity index 100%
rename from mistral/utils/serializer.py
rename to mistral/utils/serializers.py
diff --git a/mistral/workflow/utils.py b/mistral/workflow/utils.py
index d8d5ca80..0b10e353 100644
--- a/mistral/workflow/utils.py
+++ b/mistral/workflow/utils.py
@@ -12,7 +12,7 @@
 #    See the License for the specific language governing permissions and
 #    limitations under the License.
 
-from mistral.utils import serializer
+from mistral.utils import serializers
 from mistral.workbook.v2 import tasks as v2_tasks_spec
 from mistral.workflow import states
 
@@ -38,7 +38,7 @@ class Result(object):
         return self.data == other.data and self.error == other.error
 
 
-class ResultSerializer(serializer.Serializer):
+class ResultSerializer(serializers.Serializer):
     def serialize(self, entity):
         return {'data': entity.data, 'error': entity.error}