We propose to design a system to support a marketplace in which flight operators can exchange arrival slots in traffic flow management (TFM) initiatives such as airspace flow programs (AFPs) and ground delay programs (GDPs) while requiring no changes in FAA automation or procedures. The advent of AFPs in 2006 has generated many more potentially exchangeable resources that would be valued sufficiently differently by their owners to make a trade desirable. We believe that NAS users and the FAA would embrace such a marketplace and that it would enable users to collectively reduce their operating costs resulting from NAS congestion. Both FAA and NASA research has highlighted the need for efficient and equitable allocation of NAS resources and increased operational flexibility. In the past market-based mechanisms have been suggested for transferring system-imposed delay from more critical to less critical flights. No such capability is available to NAS users today. In this SBIR, we will show how the advent of AFPs changes the forces at work in a slot-trading marketplace, making its functions much more valuable to flight operators. We will also design a system that will provide the aviation community with a means of reducing operating costs and increasing effective throughput by trading scarce NAS resources.