Cigarette smoking is associated with consistent changes in small arteries and arterioles. Recently, arterial compliance was determined in smokers; however, the effect of smoking cessation on arterial compliance has not yet been investigated. The objective of the study was to assess how smoking cessation, achieved with use of behavioral and pharmacologic therapy, influences vascular compliance and arterial stiffness in smokers. In an open-label study, 60 habitual smokers were treated for 2 months with buproprion 300 mg per day and personal and group conversations in order to facilitate smoking cessation. Hemodynamic variables, including vascular compliance and augmentation index (AI), were measured twice, at the beginning of the study and after 6 months. Of the 60 smokers, 35 stopped smoking and 25 failed at the end of the 2-month treatment period. Of the 35 who were initially successful, 12 went back to smoking, and thus only 23 remained nonsmokers at the end of 6 months. Smoking cessation was accompanied by significantly lower arterial pressure and heart rate but by weight gain. Among the 23 subjects who stopped smoking for 6 months capacitive compliance (C 1) did not change but oscillatory compliance (C 2) rose significantly (from 5.1 ±2.3 to 6.3 ±3.0 p <0.01), and AI decreased significantly (from 63.1 ±22 to 50.6 ±17 p <0.05), whereas in smokers who still smoked after this period, both C 1 and C 2 and augmentation index did not change significantly from their basal values. The authors conclude that smoking cessation improves arterial stiffness as assessed by the augmentation index, owing mainly to increasing the small artery compliance, which is known to be an early index of endothelial damage.