Endometriosis is an important clinical problem in routine practice. Besides the problems of dysmenorrhea, dyspareunia and chronic abdominal pain, women with endometriosis are often infertile. We performed a systematic literature review on two issues: firstly, we clarified which medical treatment options have been investigated in prospective, randomized studies. Secondly, potential future treatments, still being preclinically investigated, were examined. A meta-analysis was not possible as the studies varied too much in their protocols and inclusion and exclusion criteria, as well as in the drugs and doses administered. Gonadotropin-releasing hormone (GnRH) agonists, progestins and oral contraceptives all appear to offer certain advantages for endometriosis patients. GnRH agonists appear to be the most effective but they are expensive and long-term treatment is not possible because of loss of bone mineral density. Estrogen add-back may offer some benefit for the clinical complaints of patients, but it may reduce the efficacy of GnRH agonists. Progestins have the best clinical profile and a good cost-effectiveness balance; however, most studies found that they were not as effective as GnRH agonists. Oral contraceptives are only effective during treatment and have a high relapse rate after therapy is completed. Future options may include the use of GnRH agonists, selective estrogen receptor modulators (SERMs) and anti-estrogens, as well as immunomodulators.