During one year in a private practice, 102 cases of childhood urinary-tract infection (UTI) were detected. Presenting symptoms and signs are given, and the sex and age of the children are related to bacterial and pus-cell counts in the urine. The urine was cultured in 68 cases, and eight patients were further investigated.Routine urinalysis and the physician's unceasing alertness are essential to diagnose and treat UTI in its early stages in children, and thus prevent renal disease in later life. The authors describe a simple practical routine by which the family doctor can detect the infection in children, and they outline preferred treatment schedules.