This white paper summarizes the state-of-knowledge and state-of-the-art in pavement life cycle assessment (LCA) modeling, with particular emphasis on life cycle greenhouse gas (GHG) emissions and on interpretation and analysis that lead to GHG reductions from the on-road transportation sector. The paper synthesizes research from a number of previous and current projects, highlighting both broadly agreed upon methods and findings, and those that are emerging or currently debated. It lists a number of recommendations for applying LCA to policy.