DHInfrastructure assisted in the development and implementation of a framework for estimating the “barrier removal costs” (effectively, all non-capital costs) of World Bank/GEF energy efficiency projects. The purpose of the study was to provide policymakers and World Bank staff with more complete information on the options presented in marginal abatement cost (MAC) curves. DHInfrastructure advised on the development of the conceptual framework, prepared a survey of experts in the energy efficiency field, and analyzed the correlation between project costs and other factors thought to be drivers of barrier removal costs.