This influence of prolongea isolation in an extreme environment on depressive symptoms, personality, and coping resources was examined in 121 members of the United States Antarctic Program in 1988–1989. Subjects were followed for a 1-year period in Antarctica. Winter-over personnel experienced an increase in depressive symptoms, avoidance as a coping method, and emotional discharge as a coping resource from baseline (T0) to Year-1 (T1). At T0, education, negative life events, job-related stress, low self-confidence, active cognitive and behavioral coping methods, and low satisfaction with social support were independent predictors of depressive symptoms. At T1, negative life events, low self-confidence, active behavioral and avoidance coping methods, affective regulation as a coping resource, and low satisfaction with social support were independent predictors of depressive symptoms. However, with the exception of T0 depressive symptoms, none of the social and demographic characteristics and T0 psychosocial measures predicted T1 depressive symptoms. The results of this study support the hypothesis that coping may be more strongly associated with environmental conditions that influence severity of stressor and availability of coping resources than with more remote and stable background factors.