It is becoming increasingly evident that STOL aircraft operating into metropolitan Stolports will make a significant contribution to the development of short haul air transport in and about metropolitan areas.A consideration of aircraft operating costs and the costs of providing metropolitan terminals shows that terminal costs are a minor part of the total system cost, with the result that the difference between VTOL and STOL indirect costs is negligible. Therefore, STOL aircraft are generally preferred over VTOL for these operations because of lower direct operating costs. The availability and proved reliability of STOL aircraft reinforce this conclusion, and it is unlikely to be altered by near term future developments.STOL operating regulations and safety aspects become a critical development to be achieved before extensive Stolport operations become widespread. Procedures for determining the take-off and landing field lengths required for the operation of small (under 12,500 lb) commercial transport aircraft into Stolports are examined.IFR operations are expected to pose initial problems because of the inadequacy of present terminal guidance equipment. It is anticipated that microwave equipment should reduce this problem. STOL aircraft are shown to possess low speed handling qualities that significantly ease the task of landing in IFR conditions.