AbstractThe intention of this article is to consider the possible clinical applications of relatively low-energy electron beams. It would appear that the main fields of application may lie in the treatment of large areas of the body surface, skin and superficial tumours and the post-mastectomy chest wall. The main advantages and disadvantages of electron therapy in these situations are discussed. The possible role of electrons in treating the post-mastectomy chest wall is considered in greater detail with particular reference to the potential danger of post-radiation fibrosis in the lungs.It is concluded that the advantages of the depth dose characteristics of low-energy electron beams may be sufficient to outweigh the disadvantages, particularly the problems associated with inhomogeneous tissue, and help to establish low-energy electron therapy in the 2–10 MeV range as having a significant, although rather limited place, in radiotherapeutic practice.