A review of the literature on cases of neurofibromatosis of the bladder is given. Eighteen cases have been recorded in adults, three of which were confined to the bladder wall, and fifteen, associated with multiple cutaneous lesions. Six cases of neurofibromatosis of the bladder have been recorded in childhood, four of these with generalised involvement and two affecting only the bladder. A further two instances, both with bladder involvement, are reported from The Hospital for Sick Children, Great Ormond Street. One of these has been treated by means of radical surgery. The etiological relationship of these lesions to the pelvic plexuses is discussed.