diff --git a/lib/kafka/consumer.rb b/lib/kafka/consumer.rb
index 6768089a0..e47232786 100644
--- a/lib/kafka/consumer.rb
+++ b/lib/kafka/consumer.rb
@@ -4,6 +4,7 @@
 require "kafka/offset_manager"
 require "kafka/fetcher"
 require "kafka/pause"
+require "concurrent"
 
 module Kafka
 
diff --git a/ruby-kafka.gemspec b/ruby-kafka.gemspec
index 2589e97d5..bac3475a7 100644
--- a/ruby-kafka.gemspec
+++ b/ruby-kafka.gemspec
@@ -28,6 +28,7 @@ Gem::Specification.new do |spec|
   spec.require_paths = ["lib"]
 
   spec.add_dependency 'digest-crc'
+  spec.add_dependency 'concurrent-ruby', '~> 1.0', '>= 1.0.2'
 
   spec.add_development_dependency "bundler", ">= 1.9.5"
   spec.add_development_dependency "rake", "~> 10.0"