BACKGROUND:: This study describes a general-practice-based high-risk cardiovascular prevention approach in Maastricht, The Netherlands (1999-2003). The intervention consisted of a complete registration of risk factors, optimization of medical treatment and health counseling on high fat consumption, smoking and physical inactivity. METHODS:: Behavioral effects were assessed in a trial, randomization by practice and usual care as control. Validated questionnaires were completed by 1300 patients at baseline, 1174 after 4 months (90.3%) and 1046 (80.5%) after 18 months. RESULTS:: After 4 months, intention-to-treat analyses revealed a decrease in saturated fat intake of 1.3 points (scale ranging from 7 to 30 points, p=0.000). This was partly sustained after 18 months (-0.5 points, p=0.014). After 18 months, obese intervention patients were more likely to be sufficiently physically active than their control counterparts (OR=1.90, p=0.023). No intervention effects were found for smoking. CONCLUSION:: Given the multiple factor and multiple component high-risk approach, the intervention had modest effects on only some of the behavioral risk factors addressed. Process data showed that the registration of risk factors and the optimization of medical treatment were only partly implemented, that the health counseling component could be further improved and that the intervention could benefit from additional health promoting strategies.