Forty-six patients with papillary carcinoma of the endometrium were studied. Forty-five were followed for at least five years or until death, and 41 were followed for 10 years. The remaining patient was alive at four years. The survival rate was 51.1% at five years and 46.3% at 10 years. At five years one-third had died of their disease. The median age at time of diagnosis was 63 years, and the age at diagnosis was an important determinant of survival. None of the seven black women survived for five years. Tumor grade was an important predictor of the course of disease and nuclear grading was a significantly more accurate indicator than was the histologic grading of the World Health Organization. Papillary carcinoma should be distinguished from the papillary type of clear cell carcinoma of the endometrium. While it has a somewhat better prognosis than mixed adenosquamous carcinoma or clear cell carcinoma, it appears to be more aggressive with a lower survival rate and higher rate of death from disease than the usual type of endometrial adenocarcinoma or adenoacanthoma.