This chapter focuses on the relationship between humor and second language (L2) development. Educational research in general has not prioritized the study of humor. In the mid-1990s, however, two developments in applied linguistics came together to bring about a new interest in non-serious language. First, sociocultural theory was becoming an important way of understanding L2 development. The second development contributing to the rise of interest in L2 humor research was concern with the idea of certain language as more "authentic" or "appropriate" for language learning. Establishing a clear role for humor in education has been challenging; however, one area where it seems to have fairly clear benefits is in the emotional realm. Humor occurs often in peer interactions, and in addition to raising awareness and memorability of L2 forms and functions, it also creates a discourse context that is both demanding and entertaining. Humor is no longer the marginalized topic it once was in applied linguistic research.