Abnormal uterine bleeding is a common problem, and its management can be complex. Because of this complexity, concise guidelines have been difficult to develop. We constructed a concise but comprehensive algorithm for the management of abnormal uterine bleeding between menarche and menopause that was based on a systematic review of the literature as well as the actual management of patients seen in a gynecology clinic. We started by drafting an algorithm that was based on a MEDLINE search for relevant reviews and original research. We compared this algorithm to the actual care provided to a random sample of 100 women with abnormal bleeding who were seen in a university gynecology clinic. Discrepancies between the algorithm and actual care were discussed during audiotaped meetings among the 4 investigators (2 family physicians and 2 gynecologists). The audiotapes were used to revise the algorithm. After 3 iterations of this process (total of 300 patients), we agreed on a final algorithm that generally followed the practices we observed, while maintaining consistency with the evidence. In clinic, the gynecologists categorized the patient's bleeding pattern into 1 of 4 types: irregular bleeding, heavy but regular bleeding (menorrhagia), severe acute bleeding, and abnormal bleeding associated with a contraceptive method. Subsequent management involved both diagnostic and treatment interventions, which often occurred simultaneously. The algorithm in this article is designed to help primary care physicians manage abnormal uterine bleeding using strategies that are consistent with the evidence as well as the actual practice of gynecologists.