diff --git a/constraints.txt b/constraints.txt
new file mode 100644
index 0000000..b626e39
--- /dev/null
+++ b/constraints.txt
@@ -0,0 +1 @@
+# Pin versions of packages that behave badly only for us
diff --git a/requirements.txt b/requirements.txt
index f09827c..05754fa 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -2,9 +2,9 @@
 # of appearance. Changing the order has an impact on the overall integration
 # process, which may cause wedges in the gate later.
 
-pbr>=1.6
-Jinja2>=2.8  # BSD License (3 clause)
-python-etcd
-PyYAML>=3.1.0  # MIT
-six>=1.9.0  # MIT
-netifaces>=0.10.4  # MIT
+pbr>=1.6 # Apache-2.0
+Jinja2>=2.8 # BSD License (3 clause)
+python-etcd>=0.4.3 # MIT License
+PyYAML>=3.10.0 # MIT
+six>=1.9.0 # MIT
+netifaces>=0.10.4 # MIT
diff --git a/setup.py b/setup.py
index 056c16c..782bb21 100644
--- a/setup.py
+++ b/setup.py
@@ -25,5 +25,5 @@ except ImportError:
     pass
 
 setuptools.setup(
-    setup_requires=['pbr'],
+    setup_requires=['pbr>=1.8'],
     pbr=True)
diff --git a/test-requirements.txt b/test-requirements.txt
index 21a7e3b..60c1484 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -4,11 +4,11 @@
 
 hacking<0.11,>=0.10.0
 
-coverage>=3.6
-python-subunit>=0.0.18
-sphinx!=1.2.0,!=1.3b1,<1.3,>=1.1.2
-oslosphinx>=2.5.0 # Apache-2.0
+coverage>=3.6 # Apache-2.0
+python-subunit>=0.0.18 # Apache-2.0/BSD
+sphinx!=1.3b1,<1.4,>=1.2.1 # BSD
+oslosphinx>=4.7.0 # Apache-2.0
 oslotest>=1.10.0 # Apache-2.0
-testrepository>=0.0.18
-testscenarios>=0.4
-testtools>=1.4.0
+testrepository>=0.0.18 # Apache-2.0/BSD
+testscenarios>=0.4 # Apache-2.0/BSD
+testtools>=1.4.0 # MIT
diff --git a/tox.ini b/tox.ini
index d130d69..c917dd9 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,11 +1,11 @@
 [tox]
-minversion = 1.6
+minversion = 1.7
 envlist = py34,py27,pep8
 skipsdist = True
 
 [testenv]
 usedevelop = True
-install_command = pip install -U {opts} {packages}
+install_command = pip install -c {toxinidir}/constraints.txt -c{env:UPPER_CONSTRAINTS_FILE:https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt} -U {opts} {packages}
 setenv =
    VIRTUAL_ENV={envdir}
 deps =