Endometriosis, a chronic and progressive condition characterized by the presence of endometrial tissue outside the uterus, accounts for about one third of the cases of chronic pelvic pain in women. Pain in endometriosis may be due to nociceptive, inflammatory, and/or neuropathic mechanisms. The clinical presentation is often variable between patients, and diagnostic laparoscopy for visualization and biopsy of lesions is the gold standard for diagnosis. The treatment may consist of two elements: chronic pelvic pain itself as a diagnosis and endometriosis as a disease. Hormonal therapy is used to reduce the amount of estrogen and hence reduce symptoms such as pelvic pain and dysmenorrhea. In patients with severe endometriosis, surgical removal of lesions, adhesions, and cysts and restoration of pelvic anatomy may be preferred. Both hormonal and surgical treatments have been shown to be effective in decreasing pain symptoms associated with endometriosis. A variety of analgesics, including nonsteroidal antiinflammatory drugs, opioids, tricyclic antidepressants, dual reuptake inhibitors of serotonin and norepinephrine, and antiepileptic drugs, have been used to ameliorate pain in endometriosis, with varying degrees of success. In patients with persistent symptoms, interventional pain management procedures may be performed to target the visceral and somatic organs and their innervations. Infertility is the most common complication of endometriosis. Between 10 and 20% of women with endometriosis have recurrence of the disease regardless of the treatment they receive. The recurrence of pain may be due to remodeling of the central nervous system, the role of the reproductive tract in reactivating pain, and incomplete removal or recurrence of lesions. This review contains 2 tables and 52 references Key words: chronic abdominal pain, chronic pelvic pain, dyschezia, dysmenorrhea, dyspareunia, endometrioma, endometriosis, hormonal therapy, infertility, retrograde menstruation, visceral pain