Decisions to invest in transport infrastructure projects require careful deliberation. Governments need evaluation methods to ensure that their scarce resources are allocated in a way that maximises their net return to society. How can the efficiency of allocating funds for transport infrastructure be improved? Is the widely-used approach of cost-benefit analysis appropriate? Does transport infrastructure investment have wider impacts on regional development which need to be taken into account in determining infrastructure investment priorities? Do we find evidence of such impacts in evaluations of major transport infrastructure projects? Which impacts might be included in future appraisal methods? Which impacts matter? How do evaluation frameworks match government policy objectives? This report provides insights into these key issues by analysing illustrative studies of the impacts of transport infrastructure investments.