As part of its Partnership for Pre-K Improvement (PPI) initiative, the Bill & Melinda Gates Foundation sponsored the RAND Corporation to study the cost of high-quality pre-K programming. The RAND study included three states--Oregon, Tennessee, and Washington--that were partnering with the foundation under PPI. The objective of the study was to estimate the cost per child of a high-quality publicly funded pre-K program in the United States at the state or district level, accounting for cost at the provider level and at the system level (e.g., school district or state). The study was also designed to help stakeholders understand the incremental costs associated with key program features of high-quality systems. In Appendixes A and B, the authors provide additional details about methods for cost data collection and methods for the data-based cost estimation and cost modeling processes, respectively. In Appendix C, the authors discuss how they estimated per-child costs for several key quality components. In Appendixes D and E, the authors provide the interview protocol for collecting cost data from providers and the system-level Excel tool, respectively. [For the full report, see ED612701.]