Cystoscopy was done in 45 children, 5–12 yr old, infected with Schistosoma haematobium. On the basis of urinary egg output, the children were classified as having mild, moderate, or heavy infection and the cystoscopic picture was correlated with their egg output and with their signs and symptoms. Lesions reported, in descending order of frequency, were: hyperemia, sandy patches, tubercles, ulcers, nodules, and polyps. Multiple schistosomal lesions were present in some patients and the frequency and severity of lesions correlated with the heaviness of infection. Individual variation in the severity of response to S. haematobium was observed.