In France, since 1996, any general practitioner (GP) can prescribe high-dosage buprenorphine maintenance treatment (BMT) for opioid-dependent patients. The health authorities initially provided mandatory specific training, but since 1998, such training is only delivered by specialized networks and the pharmaceutical industry. Among a random sample of GPs from southeastern France (N=345), we found that many untrained GPs, as well as a significant minority of trained GPs, were likely to prescribe an ineffective dosage of buprenorphine or a potentially dangerous treatment (BMT+a short half-life benzodiazepine). These results highlight the necessity to edit clear guidelines, especially concerning situations of polyaddiction and psychiatric comorbidity, and to extend and improve BMT training in France with a renewed involvement of health authorities for quality control of such training. They even suggest that GPs' participation to specialized training sessions should become a mandatory prerequisite for prescribing BMT.