Child socialization and development are, in part, products of adapting cultural systems. These systems evolve from the combined influence of collective history and current environmental affordances. They permeate family systems, shaping child development via numerous mechanisms, including structures and roles; values, beliefs, and goals; and parenting-to name a few. Recent growth in the study of child development among racial, ethnic, and cultural minority groups, which has been supported by important cultural-developmental theoretical advances, sheds essential light on the ways in which adapting cultural systems permeate child socialization and development in all families. Across this scholarship, there are numerous examples of the effectiveness of adapting cultural systems for promoting developmental competencies. There are also examples, however, in which adapting cultural systems either fail to promote developmental competencies or undermine the development of competencies. To address these theoretical and empirical tensions, we advance a set of propositions. Together, the propositions situate the developmental consequences of adapting cultural systems within multiple scientific traditions, including psychological, ecological, family systems, developmental, and biological perspectives. These propositions can support scientific inquiries aimed at identifying both the benefits and costs of adaptive cultures for development among diverse groups. (PsycINFO Database Record