This study investigates the relationships among stress, coping, and mental health in 139 students participating in an International Baccalaureate (IB) high school diploma program. Mental health was assessed using both positive indicators (life satisfaction, academic achievement, academic self-efficacy) and negative indicators (psychopathology) of adolescent social-emotional and school functioning. Findings include that students in an IB program perceive significantly more stress than a sample of 168 of their general education peers, and that specific coping styles are differentially related to mental health outcomes in this subgroup of high-achieving high school students. Furthermore, coping styles (specifically, anger and positive appraisal) moderate the influence of stress on global life satisfaction and internalizing symptoms of psychopathology. (Contains 4 tables and 2 figures.)