Between 1965 and 1970, 160 inoperable patients with adenocarcinoma of the endometrium were treated using intracavitary radium alone. Patients were given either two insertions (7500 cGy stated dose over 10 days), or one insertion (5000 cGy stated dose over 4 days) depending on their general condition. The FIGO stage and histological degree of differentiation had a significant influence on survival. Most patients had Stage 1 disease; 5-year and 10-year corrected survival for those having two insertions was 73% and 62% respectively, compared with 58% and 34% respectively for those having a single insertion ( p<0.015). The primary tumour control rate was greater using two insertions (77%) than with a single insertion (67%). Treatment morbidity was low. In this selected group of patients, intracavitary radium using a central intrauterine line source and vaginal ovoids produced results comparable with other reported radiotherapy techniques.