The causes, characteristics, and outcomes of depression are related to multiple psychological factors. These include individual characteristics such as cognitive style or temperament, as well as social contextual factors such as family environment and peer experiences. Challenging psychosocial factors can play an etiological or causal role in depression, and they can be a consequence of depression. Importantly, many of these psychosocial factors, including social rejection and maladaptive cognitive style, exert a particularly strong influence during adolescence, a developmental period when social, cognitive, and biological changes combine to increase the likelihood of depression.