Medication administration errors remain a common source of preventable harm for hospitalized patients. This prospective observational study of 298 pediatric nurses at one hospital in Sydney, Australia, found that errors occurred in one-third of medication administrations. Intravenous injections had highest rate of potentially serious errors (59.7%) followed by intravenous infusions (10.5%). The analysis identified several significant risk factors for medication administration errors, including intravenous route, weekend administration, and use of electronic medication management systems.