In describing vulval skin changes, all terms such as leucoplakia, kraurosis vulvae and lichen sclerosus et atrophicus should be discarded in favour of 'chronic vulval dystrophy'. Initial biopsy is mandatory to establish the precise diagnosis. From a review of the literature and from our own studies we believe that vulval dystrophy is not usually a premalignant condition, a risk of carcinoma exiting only in dystrophic vulvas with associated atypia. For such patients the treatment is local vulvectomy; otherwise, because of the high rate of recurrence of chronic vulval dystrophy following surgery, the treatment should primarily be medical. Gastrointestinal peptides have been isolated from the vulval skin and a working hypothesis of the aetiology of vulval dystrophy is presented.