A diathesis-stress model was proposed in which the joint forces of individual vulnerability (anxious solitude) and interpersonal adversity (peer exclusion) predict depressive symptoms in children over time. Children's (N = 388; 50% female) social behavior, peer exclusion, and emotional adjustment were assessed at kindergarten entry and every spring thereafter through 4th grade, primarily by teacher report. Results indicated that anxious solitude and peer exclusion co-occur in children soon after kindergarten entry and that anxious solitary children who are excluded early on, in comparison with their nonexcluded anxious solitary counterparts, display greater stability in their subsequent display of anxious solitude. As hypothesized, the joint influence of anxious solitude and exclusion predicted the most elevated depressive symptom trajectories.