diff --git a/requirements.txt b/requirements.txt
index 8bae55d..4508c5e 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -11,3 +11,4 @@ requests==2.9.1
 vcrpy==1.7.4
 vdf==2.0
 sphinx==1.3.5
+six==1.10.0
diff --git a/setup.py b/setup.py
index 8cf77a4..8b76636 100644
--- a/setup.py
+++ b/setup.py
@@ -15,6 +15,7 @@ with open(path.join(here, 'steam/__init__.py'), encoding='utf-8') as f:
     __version__ = f.readline().split('"')[1]
 
 install_requires = [
+    'six>=1.10',
     'cryptography>=1.3',
     'requests>=2.9.1',
     'vdf>=2.0',