This report summarizes research findings and implementation practices for teacher and principal value-added models (VAM) as a first step in the Team Pennsylvania Foundation’s pilot project to inform the development of a full, statewide model evaluation system. The report selected 21 empirical studies that describe key issues and findings in the literature and examined varying degrees of value-added implementation in seven school districts or states. It presents information aimed at VAM development: typical data elements, important modeling considerations, features specific to teachers or principals, and broad implementation features.