We review the evidence for a genetic basis of the cardiovascular and renal stress response. A bio-behavioral model of stress-induced hypertension is presented that explains how repeated exposure to stress in combination with genetic susceptibility might lead to the development of hypertension. In this model, we focus on three underlying physiological systems that mediate the stress response of the heart, vasculature and kidney: the sympathetic nervous system (SNS), the renin-angiotensin-aldosterone system (RAAS) and the endothelial system (ES). We then review the evidence for a genetic influence on cardiovascular reactivity to psychological stress and stress-induced sodium retention using data from twin and family studies and a limited number of candidate gene studies. Finally, by describing the underlying physiological systems of our model and their genetic underpinning we emphasize the importance of inclusion of genetic measurements in any future studies testing the reactivity hypothesis.