Crohn's disease and ulcerative colitis are important disorders in childhood which may present in a similar way to adult life, but the major paediatric dimension is impairment of growth and development which may occur in both disorders. Whilst the diagnosis of ulcerative colitis is usually quite quick by virtue of the pressing nature of the chief symptoms, bloody diarrhoea, the diagnosis of Crohn's disease may be significantly delayed in children as the symptoms are frequently less obvious and may not, at first, be gastrointestinal. Modern diagnosis is based upon a combination of endoscopy and radiology. Of particular importance is endoscopic biopsy which enables a definite histological diagnosis to be made. Early referral to diagnostic centres is particularly important in childhood.