Road development cost and benefits due to changes in agricultural and industrial outputs are not directly included in HDM4. However, there are a number of countries or areas where the development and maintenance of the road networks are strongly associated with the transportation of agricultural and/or industrial outputs which play a vital role in the economies of many countries. It is important that an appropriate model dealing explicitly with this development issue is formed. This project will therefore seek to develop a model to be considered for direct inclusion in HDM4 with emphasis on rural roads. The work will include: - Literature review of agricultura land industrial outputs models - Development of a prototype model - Testing, validation and verification of the model. - Comparison with other models.