An overview is given of the Cargo/Logistics Airlift Systems Study (CLASS) project. CLASS was a 10 manyear effort carried out by two contractor teams, aimed at defining factors impacting future system growth and obtaining market requirements and design guidelines for future airfreighters. Surveys of hundreds of major shippers, airframe manufacturers, airlines, freight forwarders, and government organizations afford a comprehensive view of the present system and its growth into the next century. Growth projection was estimated by two approaches: one, an optimal systems approach with a more efficient and cost-effective system considered as being available in 1990; and other, an evolutionary approach with an econometric behavior model used to predict long-term evolution from the present system. Both approaches predict significant growth in demand for international airfreighter services and less growth for U.S. domestic services. Economic analyses of airfreighter fleet options indicate very strong market appeal of derivative widebody transports in 1990 with little incentive to develop all-new dedicated airfreighters utilizing the 1990's technology until sometime beyond the year 2000. Advanced airfreighters would be economically attractive for a wide range of payload sizes (to 500 metric tons), however, if a government would share in the RD and T costs by virture of its need for a slightly modified version of a civil airfreighter design (e.g. military airlifter).