Motivation is assumed to influence behaviors via perceived agency over goal pursuits, but empirical research integrating motivation and action-control processes in social development is close to nonexistent. We applied this perspective to the study of early adolescent friendships by examining motivation for and perceived control (ability and effort) over establishing and maintaining friendships in association with adolescents' emotional adjustment, friend-reported friendship closeness, and peer-reported social adjustment. Participants were 648 early adolescents (12-14 years). As expected, intrinsic friendship motivation was associated with perceived ability and effort in the self as well as positive adjustment, whereas extrinsic motivation was associated with relying on others in friendship tasks and poor adjustment. Motivation was also directly related to adjustment and the observed associations differed by gender. The integrated motivation-action control model was supported in terms of adolescent emotional adjustment and friendship quality. (Contains 2 figures, 1 table, and 1 note.)