Short-haul air transportation is one of the most challenging of all modes of transportation. The short-haul passenger market represents approximately 40 percent of the total U.S. domestic market. This market can be classified by passenger density. A Douglas study, funded under a NASA contract, is reviewed. This study indicates potential means for successfully meeting the challenges in the market with under 500 daily passengers. Initially, the market is investigated and realistically defined; then aircraft requirements that are economically viable and environmentally acceptable are established to satisfy the market.To meet the challenges of this market, the need for economic viability and environmental acceptability requires the careful balancing of performance, technology, and design-to-cost concepts. A general aviation manufacturer participated in evaluating design-to-cost options and three airlines provided guidance for operating realism.