Recent years have witnessed the development of a new movement within health care: the promotion of "evidence-based medicine" (EBM). EBM is about integrating individual clinical expertise and the best external evidence derived from scientific research. Advocates claim that much medical practice is based too much on opinion and experience and insufficiently on research evidence. Their approach would increase the quality of care and its efficiency. This paper describes the principal steps in the evidence-based approach-systematic reviews of the literature and meta-analyses-and its shortcomings in surgery. These include the reliance of EBM on randomized trials, the lack of generalizability of scientific evidence to individual patients, the lack of attention to third party interests, the threat to the "art" of medicine, and the dangers of an oversimplistic approach. Although EBM clearly has a place, it does not have all the answers.