Abstract This chapter provides an overview of the pain mechanisms in chronic pelvic pain (CPP) by breaking them into the categories of nociceptive pain and neuropathic pain. Very frequently, the origin of CPP is associated not only with the presence of gynecological disorders (such as endometriosis, pelvic congestion syndrome, pelvic inflammatory disease, remaining ovary syndrome, or adhesions), but also with non-gynecological diagnoses, including myofascial pain disorders, irritable bowel syndrome, interstitial cystitis/painful bladder syndrome, or fibromyalgia. Four parts of the nervous system that transmit painful signals from the periphery to superior centers of the central nervous system are discussed. Acute pain is differentiated from chronic pain. The underpinnings of pharmacological treatment of CPP are discussed, as well as the effect of estrogen on CPP.