This issue of the FAL Bulletin presents a tool for estimating demand for freight transport by using input-output tables. It shows how the method is applied in Brazil, Chile, Ecuador and Nicaragua. The estimates generated (in tons) are based on certain assumptions, such as growth associated with a certain planned level of expenditure, and provide an initial approximation to a model that should eventually include other techniques. The idea is to obtain a more accurate assessment of freight transport supply needs for strategic and operational purposes.