diff --git a/cloudkitty/collector/monasca.py b/cloudkitty/collector/monasca.py
index 2ba2070b..d14906be 100644
--- a/cloudkitty/collector/monasca.py
+++ b/cloudkitty/collector/monasca.py
@@ -67,6 +67,9 @@ MONASCA_EXTRA_SCHEMA = {
             All(str, Length(min=1)),
         Required('aggregation_method', default='max'):
             In(['max', 'mean', 'min']),
+        # In case the metrics in Monasca do not belong to the project
+        # cloudkitty is identified in
+        Required('forced_project_id', default=''): str,
     },
 }
 
@@ -177,6 +180,10 @@ class MonascaCollector(collector.BaseCollector):
         period = end - start
 
         extra_args = self.conf[metric_name]['extra_args']
+        kwargs = {}
+        if extra_args['forced_project_id']:
+            kwargs['tenant_id'] = extra_args['forced_project_id']
+
         return self._conn.metrics.list_statistics(
             name=metric_name,
             merge_metrics=True,
@@ -185,7 +192,8 @@ class MonascaCollector(collector.BaseCollector):
             end_time=ck_utils.ts2dt(end),
             period=period,
             statistics=extra_args['aggregation_method'],
-            group_by=group_by)
+            group_by=group_by,
+            **kwargs)
 
     def _fetch_metrics(self, metric_name, start, end,
                        project_id=None, q_filter=None):
diff --git a/cloudkitty/tests/__init__.py b/cloudkitty/tests/__init__.py
index d86cbca5..6a38fa59 100644
--- a/cloudkitty/tests/__init__.py
+++ b/cloudkitty/tests/__init__.py
@@ -17,6 +17,7 @@
 #
 import decimal
 
+from keystoneauth1 import session as ks_sess
 import mock
 from oslo_config import fixture as config_fixture
 from oslotest import base
@@ -82,7 +83,7 @@ class TestCase(testscenarios.TestWithScenarios, base.BaseTestCase):
         self.auth = auth
         session = mock.patch(
             'keystoneauth1.loading.load_session_from_conf_options',
-            return_value=dict())
+            return_value=ks_sess.Session())
         session.start()
         self.session = session
 
diff --git a/cloudkitty/tests/collectors/test_monasca.py b/cloudkitty/tests/collectors/test_monasca.py
new file mode 100644
index 00000000..05fdb599
--- /dev/null
+++ b/cloudkitty/tests/collectors/test_monasca.py
@@ -0,0 +1,100 @@
+# Copyright 2019 Objectif Libre
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, 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 datetime
+
+import mock
+
+from cloudkitty.collector import monasca as mon_collector
+from cloudkitty import tests
+from cloudkitty import transformer
+from cloudkitty import utils
+
+
+class MonascaCollectorTest(tests.TestCase):
+
+    def setUp(self):
+        super(MonascaCollectorTest, self).setUp()
+        self.conf.set_override('collector', 'monasca', 'collect')
+        conf = {
+            'metrics': {
+                'metric_one': {
+                    'unit': 'GiB',
+                    'groupby': ['project_id'],
+                    'extra_args': {
+                        'aggregation_method': 'max',
+                    },
+                },
+                'metric_two': {
+                    'unit': 'MiB',
+                    'groupby': ['project_id'],
+                    'extra_args': {
+                        'aggregation_method': 'max',
+                        'forced_project_id': 'project_x'
+                    },
+                },
+            }
+        }
+        with mock.patch(
+                'cloudkitty.collector.monasca.'
+                'MonascaCollector._get_monasca_endpoint',
+                return_value='http://noop'):
+            self.collector = mon_collector.MonascaCollector(
+                transformer.get_transformers(),
+                period=3600,
+                conf=conf,
+            )
+
+    def test_fetch_measures_kwargs_no_forced_project(self):
+        with mock.patch.object(self.collector._conn.metrics,
+                               'list_statistics') as m:
+            start = datetime.datetime(2019, 1, 1)
+            end = datetime.datetime(2019, 1, 1, 1)
+            self.collector._fetch_measures(
+                'metric_one',
+                utils.dt2ts(start),
+                utils.dt2ts(end),
+            )
+            m.assert_called_once_with(
+                name='metric_one',
+                merge_metrics=True,
+                dimensions={},
+                start_time=start,
+                end_time=end,
+                period=3600,
+                statistics='max',
+                group_by=['project_id', 'resource_id'],
+            )
+
+    def test_fetch_measures_kwargs_with_forced_project(self):
+        with mock.patch.object(self.collector._conn.metrics,
+                               'list_statistics') as m:
+            start = datetime.datetime(2019, 1, 1)
+            end = datetime.datetime(2019, 1, 1, 1)
+            self.collector._fetch_measures(
+                'metric_two',
+                utils.dt2ts(start),
+                utils.dt2ts(end),
+            )
+            m.assert_called_once_with(
+                name='metric_two',
+                merge_metrics=True,
+                dimensions={},
+                start_time=start,
+                end_time=end,
+                period=3600,
+                statistics='max',
+                group_by=['project_id', 'resource_id'],
+                tenant_id='project_x',
+            )
diff --git a/cloudkitty/tests/collectors/test_validation.py b/cloudkitty/tests/collectors/test_validation.py
index 031eef36..725baa1b 100644
--- a/cloudkitty/tests/collectors/test_validation.py
+++ b/cloudkitty/tests/collectors/test_validation.py
@@ -97,6 +97,7 @@ class MetricConfigValidationTest(tests.TestCase):
         expected_output['metric_one']['extra_args'] = {
             'aggregation_method': 'max',
             'resource_key': 'resource_id',
+            'forced_project_id': '',
         }
 
         self.assertEqual(
diff --git a/doc/source/admin/configuration/collector.rst b/doc/source/admin/configuration/collector.rst
index 7f0c6587..5fa6a1c1 100644
--- a/doc/source/admin/configuration/collector.rst
+++ b/doc/source/admin/configuration/collector.rst
@@ -64,6 +64,13 @@ Section: ``collector_monasca``.
 * ``monasca_service_name``: Defaults to ``monasca``. Name of the Monasca
   service in Keystone.
 
+.. note:: By default, cloudkitty retrieves all metrics from Monasca in the
+          project it is identified in. However, some metrics may need to be
+          fetched from another tenant (for example if ceilometer is publishing
+          metrics to monasca in the ``service`` tenant but monasca-agent is
+          publishing metrics to the ``admin`` tenant). See the monasca-specific
+          section in "Metric collection" below for details on how to configure
+          this.
 
 Prometheus
 ----------
@@ -259,6 +266,12 @@ Monasca
   when retrieving measures from monasca. Must be one of ``min``, ``max``,
   ``mean``.
 
+* ``forced_project_id``: Defaults to None. Force the given metric to be
+  fetched from a specific tenant instead of the one cloudkitty is identified
+  in. For example, if cloudkitty is identified in the ``service`` project, but
+  needs to fetch a metric from the ``admin`` project, its ID should be
+  specified through this option.
+
 Prometheus
 ~~~~~~~~~~
 
diff --git a/releasenotes/notes/force-project-id-monasca-collector-cb30ed073d36d40e.yaml b/releasenotes/notes/force-project-id-monasca-collector-cb30ed073d36d40e.yaml
new file mode 100644
index 00000000..fb7a94af
--- /dev/null
+++ b/releasenotes/notes/force-project-id-monasca-collector-cb30ed073d36d40e.yaml
@@ -0,0 +1,5 @@
+---
+features:
+  - |
+    It is now possible to force a project_id to retrieve a specific metric
+    from it with the monasca collector.