The clinical features of 100 cases of balanitis are described. The condition affects no more than 4% of boys, is commonest during pre-school years (but rare prior to toilet training) and is usually associated with a prepuce which is partly or completely non-retractable. It does not cause phimosis and no single pathogen is involved. Most boys suffer a single episode and circumcision is indicated only for those with recurrent, troublesome attacks.