Endometriosis is a common, benign and chronic gynecological disorder. It is also an estrogen-dependent disorder that can result in substantial morbidity, including pelvic pain, pro gressive dysmenorrhea, dyspareunia, infertility and repeat surgeries. Endometriosis is often treated surgically upon diag nosis but with a higher rate of recurrence, suggesting that a combination of surgical and medical management might provide better outcomes. The primary goal of medical treatment for endometriosis is to halt the growth and activity of endometriosis lesions. The most widely utilized medical treat ment for endometriosis involves use of gonadotropin-releasing hormone (GnRH) agonists and oral contraceptives. Conventional agents also include androgen derivates and progestins. Due to the chronic nature of this disease, long-term or Dr. Hong-Yuan Huang repeated courses of medication may be required to control its related symptoms. Increasing knowledge about the pathogenesis of endometriosis at the cellular and molecular levels may give us the opportunity to use new, specific agents for treatment, including aromatase inhibitors, progesterone antagonists, selective progesterone receptor modulators, GnRH antagonists, intrauterine releasing systems with progestin and new pharmaceutical agents affecting inflammation, angiogenesis, and matrix metalloproteinase activity. Many of these promising new agents may prevent or inhibit the development of endometriosis. Further clinical trials may determine if these new therapies are superior to current medical treatment strategies for endometriosis.