In recent years, pediatric practitioners have increasingly used ambulatory blood pressure (ABP) monitoring for evaluating blood pressure (BP) abnormalities in children. ABP monitoring in adults is superior to casual BP measurements for predicting cardiovascular morbidity and mortality, and whereas the association with target-organ damage in children is not as definitive, early evidence does seem to parallel the adult data. In addition to confirming hypertension at diagnosis, ABP monitoring may be useful for identifying isolated nocturnal hypertension, characterizing BP patterns, and assessing response to therapeutic interventions. This article reviews current evidence supporting the use of ABP monitoring in children and discusses limitations in our understanding of this technology, specifically focusing on indications for its use and interpretation of the large quantity of data obtained by ABP monitoring.