The diagnosis of acute pelvic pain in the woman of reproductive age represents a major clinical challenge. In approaching such a patient, the clinician must differentiate between pregnancy-related causes, gynecologic disorders, and nonreproductive tract causes. A careful history and physical examination, along with selective and knowledgeable use of diagnostic tests and procedures, are essential to the diagnostic process. Diagnostic laparoscopy represents the reference standard for diagnosis of many of its possible causes and can obviate the need for exploratory laparotomy. Once competing diagnoses have been adequately excluded, an empiric trial of antibiotic therapy for acute pelvic inflammatory disease, coupled with close clinical follow-up, should be considered in patients with acute pelvic pain found to have cervical motion tenderness and bilateral adnexal tenderness on examination.