Abstract: The present invention comprises a system and method for managing transportation demand and capacity. The present invention allows a carrier to perform rapid and accurate determinations of the profitability of accepting various load transporting opportunities while taking into account the effect of taking a particular load on the entire carrier network. The present invention makes these profitability determinations based on a network model which is continually updated to account for changing market conditions and the effects of real-time events. The method of the present invention includes creating a dynamic network flow model comprised of multiple nodes, each node representing a specific location at specific time. The marginal value of a unit of capacity (e.g. a truck, a trailer, a rail car, a plane, etc.) at each node is calculated by solving the dual of a linear program associated with the network flow model. A matrix is created by a dynamic network value engine (NVE).