diff --git a/mistralclient/api/base.py b/mistralclient/api/base.py
index 5bda3188..f15244b9 100644
--- a/mistralclient/api/base.py
+++ b/mistralclient/api/base.py
@@ -13,9 +13,10 @@
 #    limitations under the License.
 
 import copy
-import json
 import six
 
+from oslo_serialization import jsonutils
+
 from keystoneauth1 import exceptions
 
 urlparse = six.moves.urllib.parse
@@ -134,7 +135,7 @@ class ResourceManager(object):
 
     def _create(self, url, data, response_key=None, dump_json=True):
         if dump_json:
-            data = json.dumps(data)
+            data = jsonutils.dumps(data)
 
         try:
             resp = self.http_client.post(url, data)
@@ -148,7 +149,7 @@ class ResourceManager(object):
 
     def _update(self, url, data, response_key=None, dump_json=True):
         if dump_json:
-            data = json.dumps(data)
+            data = jsonutils.dumps(data)
 
         try:
             resp = self.http_client.put(url, data)
@@ -216,7 +217,7 @@ def get_json(response):
     if callable(json_field_or_function):
         return response.json()
     else:
-        return json.loads(response.content)
+        return jsonutils.loads(response.content)
 
 
 class APIException(Exception):
diff --git a/mistralclient/api/v2/action_executions.py b/mistralclient/api/v2/action_executions.py
index 628bdc13..ef98261f 100644
--- a/mistralclient/api/v2/action_executions.py
+++ b/mistralclient/api/v2/action_executions.py
@@ -12,7 +12,7 @@
 #    See the License for the specific language governing permissions and
 #    limitations under the License.
 
-import json
+from oslo_serialization import jsonutils
 
 from mistralclient.api import base
 
@@ -30,10 +30,10 @@ class ActionExecutionManager(base.ResourceManager):
         data = {'name': name}
 
         if input:
-            data['input'] = json.dumps(input)
+            data['input'] = jsonutils.dumps(input)
 
         if params:
-            data['params'] = json.dumps(params)
+            data['params'] = jsonutils.dumps(params)
 
         return self._create(
             '/action_executions',
diff --git a/mistralclient/api/v2/cron_triggers.py b/mistralclient/api/v2/cron_triggers.py
index 13e8e135..71672072 100644
--- a/mistralclient/api/v2/cron_triggers.py
+++ b/mistralclient/api/v2/cron_triggers.py
@@ -12,8 +12,7 @@
 #    See the License for the specific language governing permissions and
 #    limitations under the License.
 
-import json
-
+from oslo_serialization import jsonutils
 from oslo_utils import uuidutils
 
 from mistralclient.api import base
@@ -47,10 +46,10 @@ class CronTriggerManager(base.ResourceManager):
             data.update({'workflow_name': workflow_identifier})
 
         if workflow_input:
-            data.update({'workflow_input': json.dumps(workflow_input)})
+            data.update({'workflow_input': jsonutils.dumps(workflow_input)})
 
         if workflow_params:
-            data.update({'workflow_params': json.dumps(workflow_params)})
+            data.update({'workflow_params': jsonutils.dumps(workflow_params)})
 
         return self._create('/cron_triggers', data)
 
diff --git a/mistralclient/api/v2/environments.py b/mistralclient/api/v2/environments.py
index 8e7a756f..5b6a493e 100644
--- a/mistralclient/api/v2/environments.py
+++ b/mistralclient/api/v2/environments.py
@@ -12,9 +12,10 @@
 #    See the License for the specific language governing permissions and
 #    limitations under the License.
 
-import json
 import six
 
+from oslo_serialization import jsonutils
+
 from mistralclient.api import base
 from mistralclient import utils
 
@@ -26,7 +27,7 @@ class Environment(base.Resource):
         """Override loading of the "variables" attribute from text to dict."""
         for k, v in self._data.items():
             if k == 'variables' and isinstance(v, six.string_types):
-                v = json.loads(v)
+                v = jsonutils.loads(v)
 
             try:
                 setattr(self, k, v)
@@ -50,7 +51,7 @@ class EnvironmentManager(base.ResourceManager):
 
         # Convert dict to text for the variables attribute.
         if isinstance(kwargs['variables'], dict):
-            kwargs['variables'] = json.dumps(kwargs['variables'])
+            kwargs['variables'] = jsonutils.dumps(kwargs['variables'])
 
         return self._create('/environments', kwargs)
 
@@ -66,7 +67,7 @@ class EnvironmentManager(base.ResourceManager):
 
         # Convert dict to text for the variables attribute.
         if kwargs.get('variables') and isinstance(kwargs['variables'], dict):
-            kwargs['variables'] = json.dumps(kwargs['variables'])
+            kwargs['variables'] = jsonutils.dumps(kwargs['variables'])
 
         return self._update('/environments', kwargs)
 
diff --git a/mistralclient/api/v2/event_triggers.py b/mistralclient/api/v2/event_triggers.py
index e20df26c..f2880448 100644
--- a/mistralclient/api/v2/event_triggers.py
+++ b/mistralclient/api/v2/event_triggers.py
@@ -12,7 +12,7 @@
 #    See the License for the specific language governing permissions and
 #    limitations under the License.
 
-import json
+from oslo_serialization import jsonutils
 
 from mistralclient.api import base
 
@@ -40,10 +40,10 @@ class EventTriggerManager(base.ResourceManager):
         }
 
         if workflow_input:
-            data.update({'workflow_input': json.dumps(workflow_input)})
+            data.update({'workflow_input': jsonutils.dumps(workflow_input)})
 
         if workflow_params:
-            data.update({'workflow_params': json.dumps(workflow_params)})
+            data.update({'workflow_params': jsonutils.dumps(workflow_params)})
 
         return self._create('/event_triggers', data)
 
diff --git a/mistralclient/api/v2/executions.py b/mistralclient/api/v2/executions.py
index b62e1b25..c65bd62c 100644
--- a/mistralclient/api/v2/executions.py
+++ b/mistralclient/api/v2/executions.py
@@ -13,9 +13,9 @@
 #    See the License for the specific language governing permissions and
 #    limitations under the License.
 
-import json
 import six
 
+from oslo_serialization import jsonutils
 from oslo_utils import uuidutils
 
 from mistralclient.api import base
@@ -53,10 +53,10 @@ class ExecutionManager(base.ResourceManager):
             if isinstance(workflow_input, six.string_types):
                 data.update({'input': workflow_input})
             else:
-                data.update({'input': json.dumps(workflow_input)})
+                data.update({'input': jsonutils.dumps(workflow_input)})
 
         if params:
-            data.update({'params': json.dumps(params)})
+            data.update({'params': jsonutils.dumps(params)})
 
         return self._create('/executions', data)
 
diff --git a/mistralclient/api/v2/tasks.py b/mistralclient/api/v2/tasks.py
index ae590ce0..780eb8c4 100644
--- a/mistralclient/api/v2/tasks.py
+++ b/mistralclient/api/v2/tasks.py
@@ -13,7 +13,7 @@
 #    See the License for the specific language governing permissions and
 #    limitations under the License.
 
-import json
+from oslo_serialization import jsonutils
 
 from mistralclient.api import base
 
@@ -60,6 +60,6 @@ class TaskManager(base.ResourceManager):
         }
 
         if env:
-            body['env'] = json.dumps(env)
+            body['env'] = jsonutils.dumps(env)
 
         return self._update(url, body)
diff --git a/mistralclient/commands/v2/action_executions.py b/mistralclient/commands/v2/action_executions.py
index 8ae9ba02..e4be423c 100644
--- a/mistralclient/commands/v2/action_executions.py
+++ b/mistralclient/commands/v2/action_executions.py
@@ -14,9 +14,10 @@
 #    under the License.
 #
 
-import json
 import logging
 
+from oslo_serialization import jsonutils
+
 from osc_lib.command import command
 
 from mistralclient.commands.v2 import base
@@ -259,8 +260,8 @@ class GetOutput(command.Command):
         output = mistral_client.action_executions.get(parsed_args.id).output
 
         try:
-            output = json.loads(output)
-            output = json.dumps(output, indent=4) + "\n"
+            output = jsonutils.loads(output)
+            output = jsonutils.dumps(output, indent=4) + "\n"
         except Exception:
             LOG.debug("Task result is not JSON.")
 
@@ -284,8 +285,8 @@ class GetInput(command.Command):
         result = mistral_client.action_executions.get(parsed_args.id).input
 
         try:
-            result = json.loads(result)
-            result = json.dumps(result, indent=4) + "\n"
+            result = jsonutils.loads(result)
+            result = jsonutils.dumps(result, indent=4) + "\n"
         except Exception:
             LOG.debug("Task result is not JSON.")
 
diff --git a/mistralclient/commands/v2/environments.py b/mistralclient/commands/v2/environments.py
index 8ae8039e..9c1bbeb9 100644
--- a/mistralclient/commands/v2/environments.py
+++ b/mistralclient/commands/v2/environments.py
@@ -13,7 +13,8 @@
 #    limitations under the License.
 
 import argparse
-import json
+
+from oslo_serialization import jsonutils
 
 from osc_lib.command import command
 
@@ -48,7 +49,7 @@ class EnvironmentFormatter(base.MistralFormatter):
             else:
                 data += (None,)
             if not lister:
-                data += (json.dumps(environment.variables, indent=4),)
+                data += (jsonutils.dumps(environment.variables, indent=4),)
             data += (
                 environment.scope,
                 environment.created_at,)
@@ -113,7 +114,7 @@ class Get(command.ShowOne):
             data = (environment.name,
                     environment.description,
                     environment.scope,
-                    json.dumps(environment.variables))
+                    jsonutils.dumps(environment.variables))
 
             return columns, data
 
diff --git a/mistralclient/commands/v2/executions.py b/mistralclient/commands/v2/executions.py
index 4af5105e..74cc551c 100644
--- a/mistralclient/commands/v2/executions.py
+++ b/mistralclient/commands/v2/executions.py
@@ -17,10 +17,11 @@
 #    under the License.
 #
 
-import json
 import logging
 import os.path
 
+from oslo_serialization import jsonutils
+
 from osc_lib.command import command
 
 from mistralclient.commands.v2 import base
@@ -296,8 +297,8 @@ class GetInput(command.Command):
         ex_input = mistral_client.executions.get(parsed_args.id).input
 
         try:
-            ex_input = json.loads(ex_input)
-            ex_input = json.dumps(ex_input, indent=4) + "\n"
+            ex_input = jsonutils.loads(ex_input)
+            ex_input = jsonutils.dumps(ex_input, indent=4) + "\n"
         except Exception:
             LOG.debug("Execution input is not JSON.")
 
@@ -320,8 +321,8 @@ class GetOutput(command.Command):
         output = mistral_client.executions.get(parsed_args.id).output
 
         try:
-            output = json.loads(output)
-            output = json.dumps(output, indent=4) + "\n"
+            output = jsonutils.loads(output)
+            output = jsonutils.dumps(output, indent=4) + "\n"
         except Exception:
             LOG.debug("Execution output is not JSON.")
 
diff --git a/mistralclient/commands/v2/tasks.py b/mistralclient/commands/v2/tasks.py
index e7f608e5..0951b388 100644
--- a/mistralclient/commands/v2/tasks.py
+++ b/mistralclient/commands/v2/tasks.py
@@ -15,10 +15,11 @@
 #    under the License.
 #
 
-import json
 import logging
 import os.path
 
+from oslo_serialization import jsonutils
+
 from osc_lib.command import command
 
 from mistralclient.commands.v2 import base
@@ -126,8 +127,8 @@ class GetResult(command.Command):
         result = mistral_client.tasks.get(parsed_args.id).result
 
         try:
-            result = json.loads(result)
-            result = json.dumps(result, indent=4) + "\n"
+            result = jsonutils.loads(result)
+            result = jsonutils.dumps(result, indent=4) + "\n"
         except Exception:
             LOG.debug("Task result is not JSON.")
 
@@ -150,8 +151,8 @@ class GetPublished(command.Command):
         result = mistral_client.tasks.get(parsed_args.id).published
 
         try:
-            result = json.loads(result)
-            result = json.dumps(result, indent=4) + "\n"
+            result = jsonutils.loads(result)
+            result = jsonutils.dumps(result, indent=4) + "\n"
         except Exception:
             LOG.debug("Task result is not JSON.")
 
diff --git a/mistralclient/tests/unit/test_client.py b/mistralclient/tests/unit/test_client.py
index 8bb5903b..473f868a 100644
--- a/mistralclient/tests/unit/test_client.py
+++ b/mistralclient/tests/unit/test_client.py
@@ -13,11 +13,11 @@
 #    See the License for the specific language governing permissions and
 #    limitations under the License.
 
-import json
 import os
 import tempfile
 
 import mock
+from oslo_serialization import jsonutils
 from oslo_utils import uuidutils
 from oslotest import base
 import osprofiler.profiler
@@ -40,7 +40,7 @@ class BaseClientTests(base.BaseTestCase):
         keystone_client_instance.auth_token = uuidutils.generate_uuid()
         keystone_client_instance.project_id = uuidutils.generate_uuid()
         keystone_client_instance.user_id = uuidutils.generate_uuid()
-        keystone_client_instance.auth_ref = str(json.dumps({}))
+        keystone_client_instance.auth_ref = str(jsonutils.dumps({}))
         return keystone_client_instance
 
     @mock.patch('keystoneauth1.session.Session')
diff --git a/mistralclient/tests/unit/test_utils.py b/mistralclient/tests/unit/test_utils.py
index 51343d6d..83f4bcd2 100644
--- a/mistralclient/tests/unit/test_utils.py
+++ b/mistralclient/tests/unit/test_utils.py
@@ -12,17 +12,17 @@
 #    See the License for the specific language governing permissions and
 #    limitations under the License.
 
-import json
 import os.path
 import tempfile
 import yaml
 
 from mistralclient import utils
+from oslo_serialization import jsonutils
 from oslotest import base
 
 
 ENV_DICT = {'k1': 'abc', 'k2': 123, 'k3': True}
-ENV_STR = json.dumps(ENV_DICT)
+ENV_STR = jsonutils.dumps(ENV_DICT)
 ENV_YAML = yaml.safe_dump(ENV_DICT, default_flow_style=False)
 
 
diff --git a/mistralclient/tests/unit/v2/test_cli_action_execs.py b/mistralclient/tests/unit/v2/test_cli_action_execs.py
index 786026c0..691aee74 100644
--- a/mistralclient/tests/unit/v2/test_cli_action_execs.py
+++ b/mistralclient/tests/unit/v2/test_cli_action_execs.py
@@ -15,13 +15,14 @@
 #
 
 import copy
-import json
 import sys
 
 import six
 
 import mock
 
+from oslo_serialization import jsonutils
+
 from mistralclient.api.v2 import action_executions as action_ex
 from mistralclient.commands.v2 import action_executions as action_ex_cmd
 from mistralclient.tests.unit import base
@@ -44,10 +45,11 @@ ACTION_EX_RESULT = {"test": "is", "passed": "successfully"}
 ACTION_EX_INPUT = {"param1": "val1", "param2": 2}
 
 ACTION_EX_WITH_OUTPUT_DICT = ACTION_EX_DICT.copy()
-ACTION_EX_WITH_OUTPUT_DICT.update({'output': json.dumps(ACTION_EX_RESULT)})
+ACTION_EX_WITH_OUTPUT_DICT.update(
+    {'output': jsonutils.dumps(ACTION_EX_RESULT)})
 
 ACTION_EX_WITH_INPUT_DICT = ACTION_EX_DICT.copy()
-ACTION_EX_WITH_INPUT_DICT.update({'input': json.dumps(ACTION_EX_INPUT)})
+ACTION_EX_WITH_INPUT_DICT.update({'input': jsonutils.dumps(ACTION_EX_INPUT)})
 
 ACTION_EX = action_ex.ActionExecution(mock, ACTION_EX_DICT)
 ACTION_EX_WITH_OUTPUT = action_ex.ActionExecution(
@@ -72,7 +74,7 @@ class TestCLIActionExecutions(base.BaseCommandTest):
 
         self.assertDictEqual(
             ACTION_EX_RESULT,
-            json.loads(self.app.stdout.write.call_args[0][0])
+            jsonutils.loads(self.app.stdout.write.call_args[0][0])
         )
 
     def test_create_save_result(self):
@@ -105,7 +107,7 @@ class TestCLIActionExecutions(base.BaseCommandTest):
 
         self.assertDictEqual(
             ACTION_EX_RESULT,
-            json.loads(self.app.stdout.write.call_args[0][0])
+            jsonutils.loads(self.app.stdout.write.call_args[0][0])
         )
 
     def test_create_run_sync_and_save_result(self):
@@ -121,7 +123,7 @@ class TestCLIActionExecutions(base.BaseCommandTest):
 
         self.assertDictEqual(
             ACTION_EX_RESULT,
-            json.loads(self.app.stdout.write.call_args[0][0])
+            jsonutils.loads(self.app.stdout.write.call_args[0][0])
         )
 
     def test_update(self):
@@ -202,7 +204,7 @@ class TestCLIActionExecutions(base.BaseCommandTest):
 
         self.assertDictEqual(
             ACTION_EX_RESULT,
-            json.loads(self.app.stdout.write.call_args[0][0])
+            jsonutils.loads(self.app.stdout.write.call_args[0][0])
         )
 
     def test_get_input(self):
@@ -212,7 +214,7 @@ class TestCLIActionExecutions(base.BaseCommandTest):
 
         self.assertDictEqual(
             ACTION_EX_INPUT,
-            json.loads(self.app.stdout.write.call_args[0][0])
+            jsonutils.loads(self.app.stdout.write.call_args[0][0])
         )
 
     def test_delete(self):
diff --git a/mistralclient/tests/unit/v2/test_cli_environments.py b/mistralclient/tests/unit/v2/test_cli_environments.py
index 539a075e..8188a03e 100644
--- a/mistralclient/tests/unit/v2/test_cli_environments.py
+++ b/mistralclient/tests/unit/v2/test_cli_environments.py
@@ -14,10 +14,11 @@
 
 import copy
 import datetime
-import json
 import os
 import tempfile
 
+from oslo_serialization import jsonutils
+
 import mock
 import yaml
 
@@ -43,7 +44,7 @@ ENVIRONMENT_DICT = {
 ENVIRONMENT = environments.Environment(mock, ENVIRONMENT_DICT)
 EXPECTED_RESULT = (ENVIRONMENT_DICT['name'],
                    ENVIRONMENT_DICT['description'],
-                   json.dumps(ENVIRONMENT_DICT['variables'], indent=4),
+                   jsonutils.dumps(ENVIRONMENT_DICT['variables'], indent=4),
                    ENVIRONMENT_DICT['scope'],
                    ENVIRONMENT_DICT['created_at'],
                    ENVIRONMENT_DICT['updated_at'])
@@ -51,7 +52,7 @@ EXPECTED_RESULT = (ENVIRONMENT_DICT['name'],
 EXPECTED_EXPORT_RESULT = (ENVIRONMENT_DICT['name'],
                           ENVIRONMENT_DICT['description'],
                           ENVIRONMENT_DICT['scope'],
-                          json.dumps(ENVIRONMENT_DICT['variables']))
+                          jsonutils.dumps(ENVIRONMENT_DICT['variables']))
 
 
 class TestCLIEnvironmentsV2(base.BaseCommandTest):
@@ -67,7 +68,7 @@ class TestCLIEnvironmentsV2(base.BaseCommandTest):
             self.assertEqual(EXPECTED_RESULT, result[1])
 
     def test_create_from_json(self):
-        self._test_create(json.dumps(ENVIRONMENT_DICT, indent=4))
+        self._test_create(jsonutils.dumps(ENVIRONMENT_DICT, indent=4))
 
     def test_create_from_yaml(self):
         yml = yaml.dump(ENVIRONMENT_DICT, default_flow_style=False)
@@ -87,7 +88,7 @@ class TestCLIEnvironmentsV2(base.BaseCommandTest):
         env = copy.deepcopy(ENVIRONMENT_DICT)
         del env['created_at']
         del env['updated_at']
-        self._test_update(json.dumps(env, indent=4))
+        self._test_update(jsonutils.dumps(env, indent=4))
 
     def test_update_from_yaml(self):
         env = copy.deepcopy(ENVIRONMENT_DICT)
diff --git a/mistralclient/tests/unit/v2/test_cli_tasks.py b/mistralclient/tests/unit/v2/test_cli_tasks.py
index 08cdda1a..9075f72b 100644
--- a/mistralclient/tests/unit/v2/test_cli_tasks.py
+++ b/mistralclient/tests/unit/v2/test_cli_tasks.py
@@ -15,7 +15,7 @@
 #    under the License.
 #
 
-import json
+from oslo_serialization import jsonutils
 
 import mock
 
@@ -39,9 +39,9 @@ TASK_RESULT = {"test": "is", "passed": "successfully"}
 TASK_PUBLISHED = {"bar1": "val1", "var2": 2}
 
 TASK_WITH_RESULT_DICT = TASK_DICT.copy()
-TASK_WITH_RESULT_DICT.update({'result': json.dumps(TASK_RESULT)})
+TASK_WITH_RESULT_DICT.update({'result': jsonutils.dumps(TASK_RESULT)})
 TASK_WITH_PUBLISHED_DICT = TASK_DICT.copy()
-TASK_WITH_PUBLISHED_DICT.update({'published': json.dumps(TASK_PUBLISHED)})
+TASK_WITH_PUBLISHED_DICT.update({'published': jsonutils.dumps(TASK_PUBLISHED)})
 
 TASK = tasks.Task(mock, TASK_DICT)
 TASK_WITH_RESULT = tasks.Task(mock, TASK_WITH_RESULT_DICT)
@@ -85,7 +85,7 @@ class TestCLITasksV2(base.BaseCommandTest):
 
         self.assertDictEqual(
             TASK_RESULT,
-            json.loads(self.app.stdout.write.call_args[0][0])
+            jsonutils.loads(self.app.stdout.write.call_args[0][0])
         )
 
     def test_get_published(self):
@@ -95,7 +95,7 @@ class TestCLITasksV2(base.BaseCommandTest):
 
         self.assertDictEqual(
             TASK_PUBLISHED,
-            json.loads(self.app.stdout.write.call_args[0][0])
+            jsonutils.loads(self.app.stdout.write.call_args[0][0])
         )
 
     def test_rerun(self):
diff --git a/mistralclient/tests/unit/v2/test_environments.py b/mistralclient/tests/unit/v2/test_environments.py
index b087e7b0..81e25fae 100644
--- a/mistralclient/tests/unit/v2/test_environments.py
+++ b/mistralclient/tests/unit/v2/test_environments.py
@@ -11,11 +11,13 @@
 #    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 #    See the License for the specific language governing permissions and
 #    limitations under the License.
+
 import collections
 import copy
-import json
 import os.path
 
+from oslo_serialization import jsonutils
+
 import pkg_resources as pkg
 from six.moves.urllib import parse
 from six.moves.urllib import request
@@ -52,7 +54,8 @@ class TestEnvironmentsV2(base.BaseClientV2Test):
         self.assertIsNotNone(env)
 
         expected_data = copy.deepcopy(data)
-        expected_data['variables'] = json.dumps(expected_data['variables'])
+        expected_data['variables'] = jsonutils.dumps(
+            expected_data['variables'])
 
         self.assertEqual(expected_data, self.requests_mock.last_request.json())
 
@@ -81,7 +84,8 @@ class TestEnvironmentsV2(base.BaseClientV2Test):
         self.assertIsNotNone(env)
 
         expected_data = copy.deepcopy(data)
-        expected_data['variables'] = json.dumps(expected_data['variables'])
+        expected_data['variables'] = jsonutils.dumps(
+            expected_data['variables'])
 
         self.assertEqual(expected_data, self.requests_mock.last_request.json())
 
@@ -104,7 +108,8 @@ class TestEnvironmentsV2(base.BaseClientV2Test):
         self.assertIsNotNone(env)
 
         expected_data = copy.deepcopy(data)
-        expected_data['variables'] = json.dumps(expected_data['variables'])
+        expected_data['variables'] = jsonutils.dumps(
+            expected_data['variables'])
 
         self.assertEqual(expected_data, self.requests_mock.last_request.json())
 
@@ -127,7 +132,8 @@ class TestEnvironmentsV2(base.BaseClientV2Test):
         self.assertIsNotNone(env)
 
         expected_data = copy.deepcopy(data)
-        expected_data['variables'] = json.dumps(expected_data['variables'])
+        expected_data['variables'] = jsonutils.dumps(
+            expected_data['variables'])
 
         self.assertEqual(expected_data, self.requests_mock.last_request.json())
 
diff --git a/mistralclient/tests/unit/v2/test_executions.py b/mistralclient/tests/unit/v2/test_executions.py
index 2c7c3417..9725939c 100644
--- a/mistralclient/tests/unit/v2/test_executions.py
+++ b/mistralclient/tests/unit/v2/test_executions.py
@@ -13,7 +13,7 @@
 #    See the License for the specific language governing permissions and
 #    limitations under the License.
 
-import json
+from oslo_serialization import jsonutils
 
 from mistralclient.api import base as api_base
 from mistralclient.api.v2 import executions
@@ -67,7 +67,7 @@ class TestExecutionsV2(base.BaseClientV2Test):
         body = {
             'workflow_name': EXEC['workflow_name'],
             'description': '',
-            'input': json.dumps(EXEC['input'])
+            'input': jsonutils.dumps(EXEC['input'])
         }
 
         ex = self.executions.create(
@@ -93,7 +93,7 @@ class TestExecutionsV2(base.BaseClientV2Test):
         body = {
             'workflow_id': EXEC['workflow_id'],
             'description': '',
-            'input': json.dumps(EXEC['input'])
+            'input': jsonutils.dumps(EXEC['input'])
         }
 
         ex = self.executions.create(
diff --git a/mistralclient/tests/unit/v2/test_tasks.py b/mistralclient/tests/unit/v2/test_tasks.py
index 82ceb980..92299e5e 100644
--- a/mistralclient/tests/unit/v2/test_tasks.py
+++ b/mistralclient/tests/unit/v2/test_tasks.py
@@ -13,7 +13,7 @@
 #    See the License for the specific language governing permissions and
 #    limitations under the License.
 
-import json
+from oslo_serialization import jsonutils
 
 from mistralclient.api.v2 import tasks
 from mistralclient.tests.unit.v2 import base
@@ -133,6 +133,6 @@ class TestTasksV2(base.BaseClientV2Test):
             'reset': True,
             'state': 'RUNNING',
             'id': TASK['id'],
-            'env': json.dumps({'k1': 'foobar'})
+            'env': jsonutils.dumps({'k1': 'foobar'})
         }
         self.assertDictEqual(body, self.requests_mock.last_request.json())
diff --git a/mistralclient/utils.py b/mistralclient/utils.py
index 4459765e..4653ef3b 100644
--- a/mistralclient/utils.py
+++ b/mistralclient/utils.py
@@ -13,10 +13,11 @@
 #    See the License for the specific language governing permissions and
 #    limitations under the License.
 
-import json
 import os
 import yaml
 
+from oslo_serialization import jsonutils
+
 from six.moves.urllib import parse
 from six.moves.urllib import request
 
@@ -46,7 +47,7 @@ def load_content(content):
     try:
         data = yaml.safe_load(content)
     except Exception:
-        data = json.loads(content)
+        data = jsonutils.loads(content)
 
     return data
 
@@ -83,7 +84,8 @@ def get_contents_if_file(contents_or_file_name):
 
 def load_json(input_string):
     try:
-        with open(input_string) as fh:
-            return json.load(fh)
+        # binary mode is needed due to bug/1515231
+        with open(input_string, 'r+b') as fh:
+            return jsonutils.load(fh)
     except IOError:
-        return json.loads(input_string)
+        return jsonutils.loads(input_string)