Disorders of menstruation are among the most common problems encountered in womens' health and include early, delayed and irregular menstrual cycles, painful menses and excessive menstrual bleeding, and early menopause. Their treatment presents a variety of complex challenges, especially since some of the treatments used can themselves result in further menstrual and hormonal complications. This text provides a comprehensive review of our current knowledge of the causes of these conditions, their investigation, and the treatment options available. It has been designed as a practical reference for the doctors' office or clinic, presenting the physician with a detailed account of how to assess the patient and then determine the most appropriate course of treatment, which may extend beyond pharmacologic interventions to surgery. Practice points conclude each section and summarize the most important clinical and management issues.