We propose a new concept for managing en route congestion that allows NAS customers to submit prioritized lists of alternative routing options for their flights, and provides traffic managers with a tool that algorithmically takes these customer preferences into consideration as it assigns reroutes and delays to flights subject to traffic flow constraints set by the traffic managers. This concept has the potential to reduce the workload of traffic managers, while allowing them finer control over traffic in uncertain weather situations, and giving NAS customers greater flexibility to operate their flights according to their business priorities. Perhaps one of the most significant benefits is the ability to recapture system capacity that is currently lost when severe weather (or other capacity limiting factors) does not materialize as predicted. This is due to the system "remembering" a flight's original routing preference. Presently this concept is being evaluated through a series of storyboards, simulations and human in the loop exercises with operational personnel from the airlines, business aviation, and traffic management communities.