Urinary tract infections (UTIs) are common in children and are associated with significant short- and long-term morbidity. They have a high recurrence rate and are associated with anatomic and functional abnormalities. The decision to test for UTI is based on risk factors and the child's age. Urinalysis is valuable to rule out UTI and to help decide when to start antibiotics; however, urine culture is needed for definitive diagnosis. Urine specimens collected via perineal bagging should not be used for culture because of high false-positive rates. Diagnosis of UTI requires pyuria and bacterial growth in the urine culture. Prompt treatment of UTIs reduces renal scarring. Antibiotic selection should be based on local sensitivity patterns and adjusted once culture results are available. In most cases, oral antibiotics are as effective as intravenous agents. When intravenous antibiotics are used, early transition to an oral regimen is as effective as longer intravenous courses. Kidney and bladder ultrasonography is helpful to identify acute complications and anatomic abnormalities. Voiding cystourethrography is indicated when ultrasound findings are abnormal and in cases of recurrent febrile UTIs. The use of antibiotic prophylaxis for recurrent UTIs is controversial. Identification and treatment of bowel and bladder dysfunction can prevent UTI recurrence.