Proulx and Chandler [this issue] provide a multifaceted contribution that is theoretical and empirical, subtle and radical, detailed and broad ranging, and deeply intertwined with fundamental issues of self, identity, personhood, agency, rationality, singularity, continuity, morality, normativity, emergence, constructivism, and development. (I hope I haven't left anything out.) This work undoubtedly advances the literature; in fact, it advances several literatures. But which literatures, and how? In this commentary I consider the implications of the empirical results for three overlapping developmental literatures: identity development, moral development, and adolescent development.