This report summarizes research findings and implementation practices for teacher and principal value-added models (VAMs), as a first step in the Team Pennsylvania Foundation's (Team PA) pilot project to inform the development of a full, statewide model evaluation system. We have selected 21 studies that represent key issues and findings in the literature and examined varying degrees of value-added implementation in seven school districts or states. The authors present information aimed at VAM development: typical data elements, important modeling considerations, features specific to teachers or principals, and broad implementation features. Three appendixes are included: (1) Article Summaries; (2) VAM Implementation in School Districts and States; and (3) Technical Description of Value-Added Models. (Contains 28 tables and 17 footnotes.)