Discrimination—the purposeful and harmful actions toward others because of their membership in a social group—can have profound effects on child and adolescent development. This chapter is concerned with mapping the literature on how perceived discrimination negatively affects a wide range of developmental processes (e.g., identity formation and prosocial behaviors) and outcomes across cognitive, physical health, socioemotional, and mental health areas. Because no such review has been written previously, we present a systematic review of this emerging body of research. We also attend to important theoretical models salient to understanding how discrimination harms children's lives, and to the social processes that may make children prone to discriminating against others. Thoughts on future research directions in this subfield accompany a discussion of the need for increased attention to the social contexts that promote discrimination in childhood and adolescence.