The cross-cultural program of research presented here is about matters of temporal persistence--personal persistence and cultural persistence--and about solution strategies for solving the paradox of "sameness-in-change." The crux of this paradox resides in the fact that, on threat of otherwise ceasing to be recognizable as a self, all of us must satisfy at least two constitutive conditions. The first of these is that selves are obliged to keep moving or die, and, so, must continually change. The second is that selves must also somehow remain the same, lest all notions of moral responsibility and any commitment to an as yet unrealized future become nonsensical. Although long understood as a problem demanding the attention of philosophers, we argue that this same paradox arises in the ordinary course of identity development and dictates the different developmental routes taken by culturally mainstream and Aboriginal youth in coming to the identity-preserving conclusion that they and others are somehow continuous through time. Findings from a set of five studies are presented. The first and second studies document the development and refinement of a method for parsing and coding what young people say on the topic of personal persistence or self-continuity. Both studies demonstrate that it is not only possible to seriously engage children as young as age 9 or 10 years in detailed and codable discussions about personal persistence, but that their reasoning concerning such matters typically proceeds in an orderly and increasingly sophisticated manner over the course of their early identity development. Our third study underscores the high personal costs of failing to sustain a workable sense of personal persistence by showing that failures to warrant self-continuity are strongly associated with increased suicide risk in adolescence. Study four documents this same relation between continuity and suicide, this time at the macrolevel of whole cultures, and shows that efforts by Aboriginal groups to preserve and promote their culture are associated with dramatic reductions in rates of youth suicide. In the final study we show that different default strategies for resolving the paradox of personal persistence and change--Narrative and Essentialist strategies--distinctly characterize Aboriginal and non-Aboriginal youth.