The absence of accepted crowding measurement tools that encompass the unique characteristics of pediatric emergency departments (EDs) creates a deficit in advancing efforts to identify and evaluate solutions for this growing problem. In this systematic review, we examined 4 studies that reported on the development and testing of multidimensional pediatric ED crowding measurements. Two investigations involved models (PEDOCS, SOTU-PED) that measured factors indicative or contributory to crowding. A third investigation developed a model mapping the flow of patients through the pediatric ED. The final study modeled the magnitude of physician’s work load, particularly when this load is high when crowding is likely present, based on patient arrivals, presenting complaints and conditions, and tests ordered. These works from 4 studies on measuring crowding in pediatric EDs show promise, but this field is at an early stage. Future work should concentrate on comparing the utility of crowding measurements across multiple pediatric ED settings.