diff --git a/requirements.txt b/requirements.txt
index a12e338..9470302 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,10 +1,10 @@
 # The order of packages is significant, because pip processes them in the order
 # of appearance. Changing the order has an impact on the overall integration
 # process, which may cause wedges in the gate later.
-pbr<2.0,>=1.6
+pbr>=1.6
 Babel>=1.3
 cliff>=1.14.0 # Apache-2.0
 oslo.i18n>=1.5.0 # Apache-2.0
-python-keystoneclient>=1.6.0
-requests>=2.5.2
+python-keystoneclient!=1.8.0,>=1.6.0
+requests!=2.8.0,!=2.9.0,>=2.5.2
 six>=1.9.0
diff --git a/setup.py b/setup.py
index d8080d0..782bb21 100644
--- a/setup.py
+++ b/setup.py
@@ -25,5 +25,5 @@ except ImportError:
     pass
 
 setuptools.setup(
-    setup_requires=['pbr>=1.3'],
+    setup_requires=['pbr>=1.8'],
     pbr=True)