Assessment of autonomic activity took place in the laboratory and during a 24 hour ambulatory measurement period. Hostility was measured with the Cook and Medley Hostility scale. The laboratory assessment helped to determine if high hostility women responded to harassment with greater cardiovascular and neurohormonal changes than low hostility women, and if this relationship was altered by 0C use, lipids, and age. The ambulatory assessment of autonomic activity allowed an exploration of the responses of high and low hostility subjects to daily-life stressors. Several hypothesis were explored: 1) Did harassment produce neuroendocrine as well as cardiovascular hyperreactivity in young women, and did this hyperreactivity generalize from laboratory to real-life? 2) Were the harassment-induced cardiovascular and neuroendocrine changes in young women also present in middle-aged women? 3) To what extent did 0C use modulate the cardiovascular and neuroendocrine responses to harassment in young women, and was 0C use also altering the hostility--related associations between lipids and reactivity? 4) Were the differential lipid-reactivity associations observed in middle-aged men as a function of high and low hostility scores present in women, and, if so, were they modulated by age?