The development of a medical risk management programme based on the aviation safety approach and its implementation in a large ambulatory healthcare organisation is described. The following key safety principles were applied: (1). errors inevitably occur and usually derive from faulty system design, not from negligence; (2). accident prevention should be an ongoing process based on open and full reporting; (3). major accidents are only the "tip of the iceberg" of processes that indicate possibilities for organisational learning. Reporting physicians were granted immunity, which encouraged open reporting of errors. A telephone "hotline" served the medical staff for direct reporting and receipt of emotional support and medical guidance. Any adverse event which had learning potential was debriefed, while focusing on the human cause of error within a systemic context. Specific recommendations were formulated to rectify processes conducive to error when failures were identified. During the first 5 years of implementation, the aviation safety concept and tools were successfully adapted to ambulatory care, fostering a culture of greater concern for patient safety through risk management while providing support to the medical staff.