This book explores the effects of cooperative teaching techniques on the comprehension and production of L2 idioms. Jigsaw, Group Investigation, and Student Teams Achievement Division techniques are those which have been chosen for this study. The study has indicated that all cooperative learning groups benefited from the use of cooperative teaching techniques, namely Jigsaw, STAD, and Group Investigation, in the learning of English idioms. The production and comprehension achievement scores of all experimental groups increased compared to that of control group.