The purpose of the study reported in this article was to tabulate the incidence and etiologic factors of importance in the development of strictures after radiotherapy for carcinoma of the esophagus and to analyze the outcome of patients who develop such strictures. Eighty patients were treated with radiotherapy, 50 having radical and 30 having palliative treatment. Sixty-nine patients had squamous cell carcinoma, four had adenocarcinoma, one had sarcoma, one had mucoepidermoid carcinoma, and five had undifferentiated tumors. Forty percent developed no stricture, 30% had benign fibrotic stricture, and 28% developed malignant stricture. The etiologic factors analysed included age, pretreatment swallowing score, histology and length (size) of tumor; stage of disease, dose of radiotherapy, and use of chemotherapy. None of these factors were shown to be of etiologic importance. The survival of patients who developed benign strictures was found to be significantly longer (1-year survival 88%) than those who developed no stricture (50%) or malignant stricture (19%). Using a "success score" for palliation of dysphagia, it was found that the majority of patients (71%) who developed a benign stricture had a moderately successful outcome--they were able to tolerate a full or soft diet and required dilatation with a median duration between dilatations of 5 months. Patients who developed a malignant stricture were palliated poorly by dilatation alone, and most required esophageal intubation.