The difficulties teachers encounter when trying to promote high quality discussion among students undoubtedly contribute to the brevity and rarity of such discussions. Teachers report that discussions fail because only a few students have usually completed the necessary preparatory work for effective participation, because some students persistently monopolize while others are silent, because their own facilitation skills are weak, and, most significantly, because what students say is often of low quality and their remarks are often off topic. Given these problems, it is not surprising that teachers question whether discussion is worth the trouble. In this article, the author addresses that question by drawing together research that (a) defines discussion, (b) clarifies the problems of implementing discussion in classrooms, (c) specifies the benefits and characteristics of effective social studies discussions, and (d) suggests what teachers can do to facilitate good discussions. The article concludes that discussion is particularly important in social studies courses because it is uniquely able to help students learn what social studies courses should be teaching. (Contains 26 notes.)