Objective: This study was undertaken to describe physicians' views regarding ambulatory medication prescribing safety. Methods: We conducted 17 semistructured interviews among a sample of practicing physicians from 3 integrated health delivery systems. We asked about current safety practices, perceptions of ambulatory prescribing safety, and recommended approaches for improving prescribing safety. Using a content analysis approach, three investigators independently coded responses into thematic categories. For 90 percent of responses, investigators agreed on the coding. Discrepant response codes were resolved through consultation among the investigators. Results: Current prescribing safety practices most frequently noted by physicians included using reference material (e.g., guidelines on hand-held devices, online drug information, electronic formulary books), verbal communication with pharmacists, and attention to educational materials on medication prescribing (posters, educational alerts, and faxes). Some subjects reported using point-of-care information technology, i.e., personal digital assistant-based drug information, as very helpful. Other subjects used pharmacy support systems. The most commonly cited safety concerns were adverse events associated with drug-drug interactions, drug allergies and side effects, prescribing for the elderly, and chronic medication use. Commonly suggested new safety approaches ranged from low-cost initiatives such as education to improve patients' knowledge of current medications (e.g., prominently placed posters reminding patients to bring medications to the visit), to more elaborate electronic medical record-based alert systems that automatically flag potential errors. Conclusions: Despite a number of safety strategies currently in use, physicians perceive significant problems with ambulatory prescribing safety. Recommended solutions range from better patient education to employing new information technology, but their effectiveness may vary depending on the underlying cause of the prescribing safety issue.