This report was prepared for the Biological Heritage National Science Challenge. New Zealand has a range of institutional arrangements for responding to a biosecurity incursion, including interventions at points in human-assisted networks such as displaying public notices, distributing information pamphlets, requiring some inspection of vehicles or passengers, or banning the transport of certain animals or commodities. Any intervention along these lines would impose costs as well as benefits. Policy advisors therefore require a robust procedure for ensuring that a possible intervention is found to be justified from a public policy perspective. The purpose of this report is to contribute to better understanding of targeted control efforts by answering the following research question: How can we evaluate the socio-economic costs and benefits, and the distribution of those costs and benefits, resulting from any proposed network intervention in response to a biosecurity incursion?