diff --git a/google-api-client.gemspec b/google-api-client.gemspec
index 17927c4c9..b154c6c9d 100644
--- a/google-api-client.gemspec
+++ b/google-api-client.gemspec
@@ -30,7 +30,8 @@ Gem::Specification.new do |s|
   s.add_runtime_dependency 'extlib', '~> 0.9'
   s.add_runtime_dependency 'launchy', '~> 2.4'
   s.add_runtime_dependency 'retriable', '~> 1.4'
-
+  s.add_runtime_dependency 'activesupport', '~> 3.2'
+  
   s.add_development_dependency 'rake', '~> 10.0'
   s.add_development_dependency 'yard', '~> 0.8'
   s.add_development_dependency 'rspec', '~> 3.1'