diff --git a/global-requirements.txt b/global-requirements.txt
index b0b95689db..d72d9a46c7 100644
--- a/global-requirements.txt
+++ b/global-requirements.txt
@@ -53,6 +53,7 @@ jsonrpclib
 jsonschema>=2.0.0,<3.0.0,!=2.5.0
 kazoo>=2.2
 keystonemiddleware>=1.5.0
+packaging>=15.2
 pyScss>=1.3.4  # MIT License
 django-pyscss>=2.0.2  # BSD License (2 clause)
 kombu>=3.0.7
diff --git a/openstack_requirements/tests/test_integration.py b/openstack_requirements/tests/test_integration.py
new file mode 100644
index 0000000000..5f1fa28c30
--- /dev/null
+++ b/openstack_requirements/tests/test_integration.py
@@ -0,0 +1,75 @@
+#    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.
+
+from packaging import specifiers
+import testtools
+
+from openstack_requirements import update
+
+
+def check_compatible(global_reqs, constraints):
+    """Check compatibility between requirements and constraints.
+
+    A change to global-requirements that wants to make changes
+    incompatible with the current frozen constraints needs to also raise
+    those constraints.
+    Load global-requirements
+    Load upper-constraints.txt
+    Check that every version within upper-constraints.txt is either
+    A) Missing from global-requirements - its a transitive dep or
+       a removed dep.
+    B) Compatible with any of the versions in global-requirements.
+       This is not-quite right, because we should in principle match
+       markers, but that requires evaluating the markers which we
+       haven't yet implemented. Being compatible with one of the
+       requirements is good enough proxy to catch most cases.
+
+    :param global_reqs: A set of global requirements after parsing.
+    :param constraints: The same from upper-constraints.txt.
+    :return: A list of the parsed package tuples that failed.
+    """
+    failures = []
+
+    def satisfied(reqs, name, version):
+        if name not in reqs:
+            return True
+        for pkg in global_reqs.values():
+            for constraint, _ in pkg:
+                spec = specifiers.SpecifierSet(constraint.specifiers)
+                if spec.contains(version):
+                    return True
+        return False
+    for pkg_constraints in constraints.values():
+        for constraint, _ in pkg_constraints:
+            name = constraint.package
+            version = constraint.specifiers[3:]
+            if not satisfied(global_reqs, name, version):
+                failures.append(constraint)
+    return failures
+
+
+class TestRequirements(testtools.TestCase):
+
+    def test_constraints_compatible(self):
+        global_req_content = open('global-requirements.txt', 'rt').read()
+        constraints_content = open('upper-constraints.txt', 'rt').read()
+        global_reqs = update._parse_reqs(global_req_content)
+        constraints = update._parse_reqs(constraints_content)
+        self.assertEqual([], check_compatible(global_reqs, constraints))
+
+    def test_check_compatible(self):
+        global_reqs = update._parse_reqs("foo>=1.2\n")
+        good_constraints = update._parse_reqs("foo===1.2.5\n")
+        bad_constraints = update._parse_reqs("foo===1.1.2\n")
+        self.assertEqual([], check_compatible(global_reqs, good_constraints))
+        self.assertNotEqual(
+            [], check_compatible(global_reqs, bad_constraints))
diff --git a/test-requirements.txt b/test-requirements.txt
index fccc225d69..bcd4e6fd0e 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -4,6 +4,7 @@
 # NOTE: These are requirements for testing the requirements project only
 #       See global-requirements for the actual requirements list
 hacking<0.11,>=0.10
+packaging
 testrepository>=0.0.18
 testscenarios>=0.4
 testtools>=1.4.0