Fifty patients sent to the Radiotherapy Service of the Mount Sinai Medical Center of New York City were interviewed by a psychiatrist. The focus of the initial interview was what they were told when referred for radiation. Although 60% were told by their doctors they had cancer, all arrived at the treatment center unprepared for the frequency, number, and procedure of treatment and for the efficacy of treatment by radiation. Patients believed that requiring radiation was very bad news. Radiation was feared as inherently damaging and quite possibly carcinogenic. Few expected it to be curative. Interviews after completing treatment revealed an incidence of depression and anxiety even greater than in the pre-treatment interviews, indicating that radiation treatment is stressful in itself. Fewer than one-third judged themselves improved by radiation. More than one-third felt worse and judged treatment to have been ineffective, not realizing their new distress resulted from side effects of radiation. Patients suffer irrational fears of damage and death because of erroneous preconceptions of radiation which doctors fail to correct. Ironically, the lay and medical concepts of the dismal manifestations and futility of radiation treatment are entirely false. In this series, only one patient suffered damage due to radiation. Sixty percent were free of signs of cancer at follow-up 18-36 months later.