Transrectal ultrasonography has proved useful in the evaluation of genitourinary disease. Experience with prostate scans has shown that such conditions as prostate carcinoma and benign prostatic hyperplasia can be diagnosed and assessed with a high degree of accuracy. In patients with carcinoma of the bladder this method is useful in determining the degree of tumor invasion within the bladder wall. Our experience with scans of the uterus is in its early stages. We have studied 30 patients with documented cervical carcinoma and are studying 1) the presence and extent of parametrial involvement, 2) the ability to distinguish benign from malignant lesions, and 3) the identification of bladder invasion.