The risk of developing a second cancer among white and black females with an initial cancer of the uterine cervix or corpus has been estimated based on the experience of the Charity Hospital of Louisiana Tumor Registry, a participant of the End Results Program of the National Cancer Institute. Observed second primary cancers were compared to expected numbers in order to obtain a direct estimate of risk. White females having an initial cancer of the cervix had a 5-to-6-fold excess risk of developing a subsequent cancer of the oral pharynx, lung, or bladder during the first 5 years following their initial cancer with no excess risk during subsequent years. Black females with cervical cancer had a 3.5-fold excess risk for developing oral cavity and lung cancer. There was no excess risk for developing subsequent cancer of the breast or large intestine, but a slight excess risk for developing subsequent cancer of the ano-rectum. There was a 7% excess risk among both whites and blacks with initial cancer of the corpus uteri of subsequently developing another cancer.