Though uncommon, infants do present with various types of voiding dysfunctions with symptoms of increased frequency, straining/crying while passing urine or recurrent urinary tract infections. Radiological findings rule out any anatomical obstruction but often do not provide adequate information regarding their diagnosis and management. i-UDS provides a valuable adjunct in these children. Performing and interpreting i-UDS may be tricky in infants as findings which are considered abnormal in a mature bladder may be physiological in infancy. This chapter deals with the practical aspects of performing and interpreting i-UDS in infants and demonstrates the same through several case studies.