INTRODUCTION As they care for patients, physicians raise questions, but they pursue only a portion of them. Without the best information and evidence, care and patient safety may be compromised. Understanding when and why problems prompt physicians to look for information and integrate results into their knowledge base is critical and shapes one part of reflection about care. This study explores the role of the Internet in gathering medical information as one step in that reflective practice, the barriers to its use, and changes in utilization over time. METHODS A questionnaire with 18 items adapted from previous studies was sent by facsimile to a randomly selected sample of U.S. physicians in all specialties and active in practice. RESULTS Specific patient problems and latest research in a specific topic most often prompt physicians to search on the Internet. Younger physicians and female physicians were most likely to seek information on a specific patient problem. Only 9% of all respondents (n = 2,500) searched for information during a patient encounter. When unsure about diagnostic and management issues for a complex case, 41.3% chose to consult with a colleague or read from a text (22.8%). Searching most often occurred at home after work (38.2%) or during breaks in the day (35.7%). Most (68.7%) found the information they were looking for more than 51% of the time. Searching was facilitated by knowing preferred sites and access in the clinical setting. The greatest barriers to answering clinical questions included a lack of specific information and too much information to scan. DISCUSSION Although physicians are increasingly successful and confident in their Internet searching to answer questions raised in patient care, few choose to seek medical information during a patient encounter. Internet information access may facilitate overall reflection on practice; physicians do not yet use this access in a just-in-time manner for immediately solving difficult patient problems but instead continue to rely on consultation with colleagues. Professional association Web sites and point-of-care databases are helpful. From physicians' use of the Internet, professionals in continuing medical education must learn which search engines and sites are trusted and preferred.