Surgery is without question the treatment of choice for the malignant melanoma (MM) of the skin. Radiotherapy, on the other hand, has been more and more neglected, especially because of the opinion that melanomas are "radioresistant". Because there is an increasing interest in the radiotherapy of MM in the recent years, and reviewing the experimental and clinical findings in the literature the following points are made: MM is not a "radioresistant" tumour and therefore the expression reduced radiosensitivity should be used instead; radiotherapy with beams of low linear energy transfer (LET) is also possible if the techniques involve the use of high dose per fraction or multiple fractions per day; different types of MM of the skin show a variable radiosensitivity in vitro and in vivo; and indications still exist for the radiotherapy of MM. All possibilities for the use of radiotherapy alone in MM have not yet been exhausted.