Acute psychophysiological stress testing, involving measurement of cardiovascular and biological responses to laboratory-induced mental stress, is an important tool to investigate mechanisms that might account for the association between psychosocial stress and cardiovascular diseases (CVD). Accumulating evidence has demonstrated associations of disturbed psychophysiological responses with sub-clinical measures of atherosclerosis, hypertension, and metabolic risk. The complex pattern of stress responding is influenced by individual differences, such as coping style, race and ethnicity, genetics, background stress, and lifestyle habits, which should be taken into account when interpreting results. For example, an unique interplay between cardiac and vascular responses in black Africans and African Americans is thought to contribute towards a heightened risk of hypertension in this group. Whether or not psychophysiological risk markers provide prognostic information over and above that of established risk markers is not clear. In summary, controlled trials that examine if the modification of psychophysiological responses through lifestyle and psychosocial interventions can reduce the risk of CVD outcomes are needed to establish causality. Further work is also required that examines the associations of ambulatory responses to real life stress in relation to risk of CVD.