This study examined relations between family cohesion and adaptability (as measured by the Family Adaptability and Cohesion Scales-III) and the formation of trust and intimacy (assessed with the Measure of Psychosocial Development) among adolescents in residential treatment. Bivariate correlation revealed a significant association between family cohesion and adaptability and psychosocial stages of trust and intimacy. Regression analyses revealed that family cohesion predicted trust, and that trust is significantly influential in the formation of intimacy. Discussion and treatment implications are included. (Contains 1 table.)