Studies comparing the cardiovascular function and stress responsiveness of regular smokers and non-smokers have produced mixed results, possibly because of variable intervals between stress tests and recency of smoking. This experiment compared the cardiovascular, cortisol and affective responses to a problem solving task of non-smoking young men (n = 16) and regular smokers randomised to overnight abstinence (n = 14) and smoking 30 min prior to testing (n = 19). Smoking status was validated biochemically. Overnight abstinence was associated with reduced diastolic blood pressure at rest and with enhanced diastolic pressure and emotional responses to the task compared with other conditions. Recent smokers showed elevated heart rates, suppressed cardiac baroreceptor reflex sensitivity and reduced cortisol responsiveness, but did not differ from non-smokers in blood pressure responses. The behavioral performance of the abstinent group was impaired, and their craving was greater than that of recent smokers. Both groups of smokers reported more dysphoric mood than non-smokers, and showed only limited recovery of emotional equilibrium following tests. The results are discussed in relation to mechanisms linking smoking, stress responsiveness and cardiovascular disease risk. The methodological implications for including regular smokers in psychophysiological studies are also considered.