The use of group work in classroom second language learning has long been supported by sound pedagogical arguments.Recently, however, a psycholinguistic rationale for group work has emerged from second language acquisition research on nonnative speaker/non-native speaker conversation, or interlanguage talk. Provided careful attention is paid to the structure of tasks students work on together, the negotiation work possible in group work makes it an attractive alternative to the teacher-led, "lockstep" mode, and a viable classroom substitute for individual conversations with native speakers.* Revised version of a paper presented at the 18th annual TESOL Convention, Houston, Texas, March 6-11, 1984 In all probability, one of the main reasons for low achievement by many classroom SL learners is simply that they do not have enough time to practice the new language. This is especially serious when teaching large classes in those EFL settings in which students need to develop aural-oral skills, but is relevant in the ESL context, too.From observational studies of classrooms, we know that the predominant mode of instruction is what might be termed the ~lockstep•, in which one person (usually the teacher) sets the same instructional pace and content for everyone, e.g. by lecturing, explaining a grammar point, leading drill work, or asking questions of the whole class. The same studies show that when lessons are organized in this manner, a typical teacher of any subject talks for at least half, and often for as much as two thirds of any class period (Flanders, 1970). In a fifty-minute lesson, that potentially leaves 25 minutes for the students.Since five minutes are usually spent on administrative matters, however, (getting pupils in and out of the room, calling the role, collecting and distributing homework assignments, etc.), and (say) five minutes on reading and writing, the total time available to students is actually more like 15 minutes. In an EFL setting, in a class of (say) 30 students in a public secondary The lockstep limits not only the gyanti~2 of talk studenta can engage in, as indicated above, but also its g.ualj~:l· This is because teacher-fronted lessons favor a highly conventionalized variety of conversation, one rarely found outside courtrooms, wedding ceremonies and classrooms. In it, one speaker asks a series of •known information", or •display" questions, such as 'Do you work in the accused's office at 27 Sloan Street?', 'Do you take this woman to be your lawful wedded wife?', and 'Do you come to class at nine o'clock?' -questions to which there is usually only one correct answer, already known 106 to both parties. The second speaker responds ('I do'), and, in the classroom, then typically has the correctness of the response confirmed ('Yes•, 'Right', or 'Good'). Only rarely is genuine communication taking place. (For further depressing details, see, e.g. Fanselow, 1977; Boetker and Ahlbrand, 1969;Long, 1975;Long and Sato, 1983;Mehan, 1979.) An unfortunate but hardly surprising side-effect of...