We investigated adolescent responsibility across 2 developmental contexts, home and an afterschool program. Longitudinal data were collected from 355 ethnically diverse 11–20-year-old adolescents (M = 15.49; 55.9% female) in 14 project-based programs. Youth rated their responsibility in the program and at home at 4 time points; parents and leaders rated youth at Time 1. The first research objective was to evaluate 3 aspects of construct validity concerning scores of responsibility assessed through a new measure. Analyses provided evidence that program- and home-responsibility scores were distinct (i.e., evidence of the structural aspect of validity); that responsibility scores were invariant across age, gender, and ethnicity (i.e., generalizability evidence); and of external validity based on parent reports (i.e., convergent evidence). The second objective was to examine cross-context transfer of responsibility. A series of cross-lagged structural equation models (SEMs) revealed that higher responsibility in each context (home, program) predicted higher responsibility in the other context, even after controlling for the stability and within-time associations. At the last time interval, the program-to-home path was significantly stronger than the corresponding home-to-program path. The third objective was to assess whether these relations were moderated by adolescent ethnicity, gender, age, or years in the program. Multigroup SEMs revealed that pathways of influence did not differ across groups. Taken as a whole, results indicate that experiences in the 2 contexts of home and program lead to interindividual differences in the development of youth self-reported responsibility, but that affordances for responsibility development across contexts change over time.