The present study delineates a method for the quantification of six hemodynamic reactivity patterns, in response to a laboratory stressor, and examines the psychophysiological correlates of individual differences in these patterns. One hundred and ninety-four young adult men and women participated in rest periods and two laboratory stressors, mental arithmetic and an anger recall interview. Measures were taken of blood pressure, heart rate, and cardiac output, from which total peripheral resistance was derived, as well as state reports of feelings during the tasks. Six hemodynamic reactor patterns were identified: Non-reactors, Mild Myocardials, Mild Vasculars, Myocardials, Vasculars, and Dual Reactors, each associated with a unique profile of cardiac output and total peripheral resistance change. Myocardial reactors to the interview had the highest resting levels of blood pressure and total peripheral resistance. Dual reactors had the largest increases in diastolic reactivity; Dual and Myocardial reactors had the largest increases in systolic reactivity. The extreme reactor groups (Dual, Myocardial, Vascular) all reported greater task invigoration than the Non-reactors, who reported greater efforts to relax. Reactor groups were similar on anger-related trait affect. Based on both resting blood pressure and magnitude of task-induced reactivity, Myocardial and Dual reactors may be at the greatest risk for subsequent hypertension.