Endometriosis is characterized by the presence of endometrial tissue, localized outside the uterine cavity, such as peritoneal surface, ovaries, and rectum-vaginal septum. The prevalence is about 6 to 10%. Concerning the etiopathogenesis, the retrograde menstruation theory is accepted, although disruption in endometrial molecular biology seems to be fundamental to the development of endometriosis ectopic focuses. Women with endometriosis may be asymptomatic or may present complaints of dysmenorrhea, dispareunia, chronic pelvic pain and/or infertility. Although the definitive diagnosis of endometriosis needs a surgical intervention, mainly by laparoscopy, many findings obtained by physicalexamination and imaging and laboratory tests can predict, with a high degree of reliability, that the patient has endometriosis. The most common current treatments include surgery, ovarian suppression therapy or both. Pharmacological treatments that do not inhibit ovarian function are under investigation.