This paper presents the results of electric aversion therapy in 24 patients with transvestism, fetishism, and sado-masochism. Preliminary findings have been reported elsewhere, together with a review of the literature and a discussion of the process of change during treatment (Marks and Gelder, 1967; Bancroft and Marks, 1968; Gelder and Marks, 1969). In these studies the available evidence indicated that the manifestations of the sexual disorder were diminished by treatment, and this appeared to be directly due to aversion rather than to non-specific components of treatment. The present report is concerned with the clinical outcome of these cases, with prognostic variables, and with the part aversion therapy should play in the treatment of these sexual disorders.