In this policy forum commentary, we call for improved national and state-level data collection and access relevant to the principal pipeline. We focus specifically on how access to quality data can inform, has informed, and is critical to policy and practice across three segments of the principal pipeline--principal preparation, licensure, and labor markets--as well as the essential issue of diversity itself and across each pipeline segment. We also outline and explain the types of data collection, storage, and access that would enable more informed and relevant principal pipeline research, policy, and preparation. We then call for action at the state and the federal levels, including reauthorization of the Higher Education Act to expand Title II educator data collection to include principal preparation programs as it does teacher preparation programs. Finally, we conclude with cautions against potential data misuse.