Psychosocial and behavioral factors, including mood (depression, anxiety, anger, and stress), personality (Type A, Type D, and hostility), and social support, are associated with both the development and progression of cardiovascular disease. "Negative" emotions have been associated with increased rates of cardiovascular death and recurrent cardiac events, although the mechanisms responsible for this association remain unclear. A number of pathophysiological mechanisms have been proposed to explain these relationships, including hypothalamic-pituitary-adrenal axis dysregulation, platelet activation, and inflammation. Behavioral factors also have been implicated, such as nonadherence to prescribed medical therapies and physical inactivity. Several randomized trials of patients with cardiovascular disease have examined the impact of pharmacologic and behavioral treatments on hard cardiovascular disease events as well as on cardiovascular disease biomarkers of risk. Although psychological treatments generally have been shown to improve quality of life and psychological functioning among cardiac patients, the benefit of psychological interventions with respect to improving clinical outcomes has not been conclusively demonstrated.