This is a randomised phase III trial which is being performed on patients at high risk of local recurrence after having a lymphadenectomy for stage 3 melanoma. The control arm is surgery alone with radiotherapy reserved for those who recur. The study arm is surgery plus post-operative radiotherapy. All 3 major node sites are eligible. The radiation dose administered is 48Gy in 20 fractions. It is likely to be the only study of its kind ever performed. The target is 230 patients.