In Ethiopia & in many parts of the world, English as a second & a foreign language students become in competent in their communication skills both in spoken & written.These incompetency are believed to become due to teachers choice & practice in language teaching methodology.To over come such challenges & work more on students' language improvement, scholars & researchers in the field of language teaching proposed different language teaching methods. Among those methods, cooperative language teaching strategy is one of the communicative language teaching which allowed students to learn the language in a cooperative & real world setting.When students learn cooperatively, they can develop interdependence, social & communicative skills. Therefore, this book provides the opportunity for students & teachers about the role & the benefit of cooperative learning. Besides,this book creates awareness for educational officers, language curriculum & syllabus designers & textbook writers to revise the curriculum, syllabus and textbook in line with the theories & approaches of communicative language teaching particularly from the point view of cooperative teaching & learning.