Recently, when one of Harvard's departments took stock of its existing undergraduate curriculum, the faculty were surprised to discover that a number of their lecture courses numbered between two and twelve students, a size more commonly found in small seminars. This raised the question of what, exactly, ought to distinguish a "lecture" course from a "seminar" of the same size. But this question, in turn, raises another, even more interesting question: why do we assume that courses of any size or nomenclature ought to correspond to any single instructional strategy? Why should any course consist wholly, or even primarily, of lectures (or discussions, or labs, or workshops, ... )? Particularly at an institution like Harvard, where many class enrollments fall somewhere in between a cozy seminar and a vast, impersonal lecture, there really is no reason why you shouldn't feel empowered to experiment with multiple strategies in the classroom, distributing the class period into segments of lecture, problem-solving, small-group discussion, and so on. As with every other aspect of teaching, you should choose your instructional strategies purposefully, with an eye to the method that seems most likely to produce the most evidence of student learning.