This paper discusses some wider implications of the UK government's Guidance on the New Approach to Appraisal. That document states that the objective of the new approach is to develop "a clear and open framework to appraise and inform the prioritisation of trunk road investment proposals". It states that choices must be made between different solutions to the same problems, and that priorities between proposals must be set. The mechanism for deciding on road schemes should strive for five characteristics, but these criteria are partly conflicting. They must be seen in the broader context of a need for a mechanism to allocate resources between competing public spending programmes and decide the total amount of public spending. The New Approach to Appraisal (NATA) is a further development of cost-benefit analysis (COBA) and other approaches in response to the continuing evolution of public understanding and opinion. There is now debate about COBA's appropriate role in the NATA. To be useful, it must gain the acceptance of those who will have to be influenced by it; this requires several compromises. The paper also discusses multicriteria analysis, `double counting', the form of an appraisal summary, and future developments.
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