45 women with a history of lower-abdominal pain of more than 6 months' duration for which no obvious cause had been found during laparoscopy (pelvic-pain syndrome) were investigated with transuterine pelvic venography. For comparison venography was carried out on 10 women in whom pathology was considered to be a likely cause for their pain and 8 women admitted for tubal ligation and who had no pain. Pelvic varicosities and congestion unrelated to parity or the menstrual cycle were commonly found in women with the pelvic-pain syndrome. A score for quantifying the severity of the pelvic vascular abnormalities has been devised; a value of 5 or more gave a diagnostic sensitivity of 91% and a specificity of 89% for the pelvic-pain syndrome.