There has been considerable debate over the extent and role of young people's political participation. Whether considering popular hand-wringing over concerns about declines in young people's institutional political participation or dismissals of young people's use of online activism, many frame youth engagement through a "youth deficit" model that assumes that adults need to politically socialize young people. However, others argue that young people are politically active and actively involved in their own political socialization, which is evident when examining youth participation in protest, participatory politics, and other forms of noninstitutionalized political participation. Moreover, social movement scholars have long documented the importance of youth to major social movements.In this article, we bring far flung literatures about youth activism together to review work on campus activism; young people's political socialization, their involvement in social movement organizations, their choice of tactics; and the context in which youth activism takes place. This context includes the growth of movement societies, the rise of fan activism, and pervasive Internet use. We argue that social movement scholars have already created important concepts (e.g., biographical availability) and questions (e.g., biographical consequences of activism) from studying young people and urge additional future research.