Extensive reading (ER) programs involve students in silently reading large quantities of material. Research suggests that extensive reading is associated with gains in first and second language proficiency. Further, extensive reading can help learners develop a reading habit and increase their level of autonomy. This paper begins with a discussion of the benefits for second language learners of combining the solitary activity of reading with group activities in which students share with classmates about what they have read. Cooperative learning is recommended as a source of principles for organizing these post-reading group activities. These cooperative learning principles include positive interdependence, individual accountability, equal participation, and simultaneous interaction. The heart of the presentation consists of a variety of post-reading group activities. The way these activities embody the cooperative learning principles is explained. Different post-reading activities are suggested for when the entire class reads the same book, when a group of students reads the same book, and when each student reads a different book. A Web site on extensive reading in second language instruction is also provided, which includes an annotated bibliography, research articles, and ideas for beginning an extensive reading program. (Contains 41 references.) (KFT)