George M. Jacobs has a PhD in Educational Psychology from the University of Hawaii and a master's degree in Linguistics from the University of Illinois--Chicago. He has been teaching courses on cooperative learning since 1988. He has published many articles on the topic and is also a coauthor of Learning Cooperative Learning via Cooperative Learning: A Sourcebook of Lesson Plans for Teacher Education (1997). He is a member of the Executive Board of the International Association for the Study of Cooperation in Education and editor of its newsletter. He also specializes in second-language learning and helped compile an annotated bibliogra-phy of works on group activities in second-language instruction. Contact him at gmjacobs@ pacific.net.sg.