In this paper we argue that the responsibility for systematic community-based preventive medicine should not be made part of the role of the general practitioner (GP). Preventive medicine cannot be shown to be more effective than curative or supportive medicine. Therefore, the allocation of the large amount of general practice staff time and resources required for systematic preventive medicine should not come at the expense of the care of the sick and the suffering. The traditional healing role of the GP requires a cooperative patient-centred approach, whereas systematic preventive medicine is driven by rigid pre-set protocols and is intrinsically paternalistic. Trying to merge the two approaches is detrimental to the doctor-patient relationship. Furthermore, a number of potential pitfalls are identified that may be encountered in the implementation of preventive medicine programmes in general practice: interference with the course of the consultation; inadequate explanation and consent; distortion of practice priorities as reflected in quality indicators; temptation to record inaccurate data; conflict of interests where the doctor is rewarded for performance; patient blaming; exacerbation of the health gap. We suggest that a more justifiable strategy would be for GPs to identify patients at high risk and offer them specific preventive advice when the opportunity presents itself and at a time when the patient is likely to be most amenable to cooperate. Opportunistic health promotion offers higher expectations of benefit, as well as a more equitable allocation of the risks associated with preventive medicine, than a systematic communitybased approach.