This paper outlines the economic surplus approach to economic impact assessment and how it may be applied to natural resource management (NRM) projects. Three challenges confront NRM impact assessment: measurement, attribution, and valuation of non-market impacts. While various methods for non-market valuation have been developed, none has yet been integrated into a market-based economic surplus analysis due to problems of measurement and theoretical consistency. Future research should address those integration problems as well as the effects on valuation of inter-country income differentials.
