To advance understanding of parents' and adolescents' unique and shared perspectives of familism, a core cultural value in Mexican-origin families, our study addressed 2 goals. First, we identified family members' unique and shared perspectives of familism values using multitrait-multimethod confirmatory factor analysis (Kenny & Kashy, 1992). Second, we examined links between family members' unique and shared perspectives of familism values and mother-youth and father-youth warmth and conflict. Participants were mothers, fathers, and 2 siblings (M[subscript age] = 15.48 years for older and M[subscript age] = 12.55 years for younger siblings) from 246 Mexican-origin families who were interviewed in their homes on 2 occasions over 5 years. Results indicated that familism values operated as an individual-level process more so than a family-level process and that youth's familism values were most consistently linked to parent-youth relationship quality. These findings provide novel insights into investigating family system dynamics involving familism values, suggest that youth's familism values may keep them connected to their families during adolescence, and highlight potential implications for prevention and intervention programs geared toward Mexican-origin families.