Recent Evolution of Research into the Wider Economic Benefits of Transport Infrastructure Investments

The debate on whether there are wider economic benefits from transport infrastructureinvestments continues to cause debate and controversy. This debate occurs both between analystsseeking to find a robust method for identifying and measuring the size of such benefits and betweenpolicy makers seeking to justify or refute the need for a particular investment. It is timely to reviewprogress on arriving at a consensus view of the contribution of infrastructure to the wider economywhich is consistent with best practice in appraisal. This paper will review progress and try to bring outsome common themes for discussion.The main aim of this paper is to bring together the various alternative methodological approachesto this problem which differs not just in the detail of the analysis, but more significantly in the scale atwhich the analysis is undertaken. It is argued that it is of particular importance to understand the wayin which changes in the provision of transport affect microeconomic decisions, including those withinfirms and households, and to understand the operation of markets as well as to model the resultantflows and their macroeconomic consequences.