The World Bank's Roads Economic Decision Model (RED) was developed under the Road Management Initiative (RMI), a key component of the Sub-Saharan Africa Transport Policy Program (SSATP) aiming at improving the decision-making process for the development and maintenance of low-volume roads. The model performs an economic evaluation of road investments options using the consumer surplus approach and is customized to the characteristics of low-volume roads such as a) the high uncertainty of the assessment of the model inputs, particularly the traffic and condition of unpaved roads, b) the importance of vehicle speeds for model validation, c) the need for a comprehensive analysis of generated and induced traffic, and d) the need to clearly define all accrued benefits. RED computes benefits for normal, generated, induced, and diverted traffic, and takes into account changes in road length, condition on the dry and wet seasons, geometry, surface type, and accident rates. Users can add to the economic analysis other benefits or costs such as social benefits and environmental impacts, if computed separately. RED is setup on a series of Excel 2000 workbooks, which collect all user inputs and present the results on an efficient manner, performing sensitivity, switching values and risk analyses. The current version of RED (Version 3.2), released in July 2004, is available in English French, and Spanish, has a new module designed to estimate vehicle operating cost using the HDM-4 relationships, permits the characterization of the traffic of the dry and wet seasons separately, and includes a budget constraint optimization and multi-criteria analysis - read more about the new features of Version 3.2. For more information about RED, read the Africa Transport Technical Notes, Note No. 18 titled 'Roads Economic Decision Model (RED) for Economic Evaluation of Low Volume Roads.'