Factors which the powerplant designer must consider in the choice of engine location are discussed, including the basic cowling and its influence on accessory disposition and pod aerodynamic performance, the engine mount, engine piping, and H.P. air ducting. A design proposal to integrate the engine and powerplant structure in order to achieve low weight and high thrust with minimum dimensions is discussed.The reliability of civil transport engines is affected by stage length. An analysis of Rolls-Royce turbojet and turbofan experience shows a distinct relationship between premature removal rate and stage length which provides a basis of comparison for engines in different operations. No such relationship has been found between shutdown rate and stage length.