diff --git a/requirements.txt b/requirements.txt
index e070e93..33052ed 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -4,7 +4,7 @@
 
 pbr!=2.1.0,>=2.0.0 # Apache-2.0
 
-eventlet!=0.18.3,>=0.18.2 # MIT
+eventlet!=0.18.3,<0.21.0,>=0.18.2 # MIT
 Flask!=0.11,<1.0,>=0.10 # BSD
 SQLAlchemy!=1.1.5,!=1.1.6,!=1.1.7,!=1.1.8,>=1.0.10 # MIT
 oslo.cache>=1.5.0 # Apache-2.0
diff --git a/test-requirements.txt b/test-requirements.txt
index 1bb66a0..36b05f2 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -13,7 +13,7 @@ hacking!=0.13.0,<0.14,>=0.12.0 # Apache-2.0
 
 coverage!=4.4,>=4.0 # Apache-2.0
 python-subunit>=0.0.18 # Apache-2.0/BSD
-sphinx>=1.5.1 # BSD
+sphinx!=1.6.1,>=1.5.1 # BSD
 oslosphinx>=4.7.0 # Apache-2.0
 oslotest>=1.10.0 # Apache-2.0
 testrepository>=0.0.18 # Apache-2.0/BSD