This environmental scan was prepared at the request of the Office of the Assistant Secretary for Planning and Evaluation (ASPE) as background information to assist the Physician-Focused Payment Model Technical Advisory Committee (PTAC) in preparing for a series of theme-based discussions on issues related to the development of larger population-based models with accountability for quality and total cost of care (TCOC). The discussion will examine key issues related to definitions, options for model design, identifying best practices, measuring and evaluating performance, and developing payment methodologies for population-based TCOC models in the broader context of Alternative Payment Models (APMs) and Physician-Focused Payment Models (PFPMs).i The environmental scan is based on information that was publicly available relating to this topic in the literature as of the time that the analysis was completed.