Endometriosis has been associated with pain and infertility. The gold standard for the diagnosis of endometriosis has been visual inspection by laparoscopy, preferably with histologic confirmation. Because there is no good noninvasive test for endometriosis, there is often a significant delay in diagnosis of this disease. Imaging that confirms an endometriotic cyst or deep infiltrating endometriosis may help guide surgical therapeutic approaches. No serum marker has been found to diagnose endometriosis with adequate sensitivity and specificity. There has been a recent focus on the presence of nerve fibers in the eutopic endometrium of patients with endometriosis.