Since the first child care Quality Rating System (QRS) was implemented in Oklahoma 11 years ago (in 1998), 16 additional statewide systems have been launched and numerous states are piloting or developing a QRS (Zaslow, Tout, & Martinez-Beck, forthcoming). As QRS stakeholders across the nation look ahead to the next decade, it is important to take stock of what has been learned and to identify priorities for generating new research and information about QRSs. The purpose of this Issue Brief is to address this need by responding to four broad questions: (1) What are the new challenges faced by QRSs?; (2) What is the status of research and evaluation on QRSs?; (3) What new information is needed to design and implement effective QRSs?; and (4) What available tools can be used as a framework to guide QRS evaluation? This Issue Brief draws on a review of the literature on QRSs, as well as the proceedings of three meetings convened by the Office of Planning, Research, and Evaluation (OPRE) in collaboration with other federal partners in the U.S. Department of Health and Human Services. The meetings brought together researchers, federal agency staff, representatives from state QRS and other quality initiatives, and a variety of stakeholders from national organizations to discuss issues related to the measurement of quality and evaluation of quality initiatives. This brief describes key themes from the meetings, then concludes with a description of follow-up steps OPRE is taking in collaboration with partners to address the issues raised. (Contains 2 footnotes.)