Perianal disease (PAD) occurs in 36% of children with Crohn's disease. Its development may precede other manifestations of the disease (3 of 26 patients). PAD ranges in severity from anal fissures and fistulae and localised perianal abscesses to extensive ischiorectal suppuration. Skin tags also occur, and although asymptomatic, may give a valuable clue to the diagnosis of Crohn's disease. Recurrent perianal or ischiorectal sepsis produce the greatest morbidity. PAD may undergo spontaneous resolution without surgical intervention. In contrast, treating patients with severe and chronic PAD may prove frustating and result in time lost from school.