This review begins with an introduction to the functions of typical airline RM systems, followed by descriptions of the types of OR models employed to perform three of the principal techniques of revenue management overbooking, fare class mix, and O-D control. Therefore, the focus of this discussion is on the seat inventory control component of airline rev- enue maximization, as virtually all airline RM systems assume that the fare structure is determined exoge nously by a separate airline pricing function.