This Brief reviews the main sources of data stakeholders at the national and state level can use to measure education levels among RNs. Each data source is described, with attention to the population of nurses or nursing graduates it represents. Nuances and shortcomings of the data are discussed to help stakeholders understand why each data source provides a different estimate of the education levels of nurses and nursing graduates and determine which data will best meet their needs in planning strategies to achieve the IOM goal.