A brief account of the clinical and histological features of keloids, their differentiation from hypertrophic scars, their etiopathogenesis, and the various methods for their treatment is followed by an assessment of the possibilities offered by cryotherapy and its advantages and drawbacks. Reference is made by way of illustration to 4 patients chosen from a series of more than 100 on the basis of the importance of their clinical pictures. The conclusion is drawn that cryotherapy with nitrogen protoxide is both useful and practical in the management of carefully selected cases and deserves fuller understanding and more widespread employment than it enjoys at present.