The authors investigated the extent to which social support and coping account for the association between greater optimism and better adjustment to stressful life events. College students of both genders completed measures of perceived stress, depression, friendship network size, and perceived social support at the beginning and end of their 1st semester of college. Coping was assessed at the end of the 1st semester. Greater optimism, assessed at the beginning of the 1st semester of college, was prospectively associated with smaller increases in stress and depression and greater increases in perceived social support (but not in friendship network size) over the course of the 1st semester of college. Mediational analyses were consistent with a model in which increases in social support and greater use of positive reinterpretation and growth contributed to the superior adjustment that optimists experienced.