Blood pressure (BP) reactivity in children, the transient elevation of BP after an acute stressor, is a stable characteristic that may predict cardiovascular disease (CVD) and hypertension. The purpose of the present study was to assess the generalizability of BP reactivity across various stressors in young children. BP reactivity was measured in 85 children (ages 3 to 6 years) after each of three different stressors. Systolic BP reactivity level was highest after physical exertion (104 mm Hg), followed by competitive task (95 mm Hg) and cognitive task (93 mm Hg). Resting systolic BP was 90. The 2-week test-retest reliability was higher for physical stress systolic BP reactivity level (r= .66) than for baseline systolic BP (r= .58) and the other two stressors. The reliability of the systolic BP change score was significant only for physical stressor (r= .33). Correlations among the three stressors ranged from .75 to .79 for systolic BP reactivity level and from .37 to .50 for change in systolic BP. Change in systolic BP after physical stress correlated with skin-fold thickness (r= .32). There was evidence of generalizability across stressors. The physical task is the most promising for future study of BP reactivity in young children.J Dev Behav Pediatr 13:41–45, 1992. Index terms:blood pressure, stress, reactivity, cardiovascular disease, children.