Public education, legislative action, and medical advances have failed to deter patients from seeking unorthodox treatments for cancer and other diseases. To study this phenomenon, we interviewed 304 cancer center inpatients and 356 patients under the care of unorthodox practitioners. A concomitant survey of unorthodox practitioners documented their backgrounds and practices. Eight percent of all patients studied never received any conventional therapy, and 54% of patients on conventional therapy also used unorthodox treatments. Forty percent of patients abandoned conventional care entirely after adopting alternative methods. Patients interviewed did not conform to the stereotype of poorly educated, end-stage patients who had exhausted conventional treatment. Practitioners also deviated from the traditional portrait: Of 138 unorthodox practitioners studied, 60% were physicians(M.D.s). Patients are attracted to therapeutic alternatives that reflect social emphasis on personal responsibility, pollution and nutrition, and that move away from perceived deficiencies in conventional medical care.