The Federal Highway Administration’s (FHWA) Research and Technology (R&T) Evaluation Program seeks to assess and communicate the benefits of FHWA’s R&T efforts; ensure that the organization is expending public resources efficiently and effectively; and build evidence to shape and improve policymaking. FHWA partners with State transportation departments, local agencies, industries, and academia to conduct research on issues of national significance and accelerate adoption and deployment of promising research products.

This report examines how FHWA’s investment in innovative intersection research through the Innovative Intersection Design program affected the availability and quality of such research; adoption of innovative intersection designs (IIDs) in the United States; and impacts of those IIDs on road-user safety, traffic mobility, and construction costs of intersections on the U.S. transportation system. The findings of this report should be of interest to engineers, practitioners, researchers, and decisionmakers involved with the research, design, performance, and management of intersections and interchanges.