Notwithstanding valiant efforts and some significant progress over the past few decades, an early care and education (ECE) workforce data deficit has endured, with persistent shortcomings in our data collection efforts at the national and state levels. Yet the early childhood field needs data-driven policy solutions. Only data can reveal inequities in access to professional development and better working conditions for early educators and inequities in access to highly qualified, well-supported early educators for children. Only data can provide the information needed to advocate for change. As illustrated by the calls for better workforce data beginning in the 1970s, the time is long overdue to prioritize a more robust ECE workforce data agenda and to advocate for the necessary resources. Toward this agenda, we describe the existing data deficit and its consequences and outline the features of comprehensive and sound data. We apply these criteria to understand the strengths and challenges of workforce registries and surveys, the most common data collection mechanisms employed by states. We also highlight several promising practices in the states to combat these challenges. (author abstract)