Conventional wisdom suggests the local cash - futures basis is determined from local supply and demand conditions. However, it may be the case that local elevators look to other locations, such as terminal locations, and adjust for transportation differentials when determining the basis for their particular market. If so, certain grain marketing locations (e.g., export and interior terminal locations) may play an important role in discovering and ultimately determining the basis for other local markets. This hypothesis is examined for the #2 yellow corn basis at various export terminal (Gulf; Toledo), river terminal (Illinois River; Omaha) and interior (S. Central Illinois; N. Central Iowa; Denver) locations. Specifically, if the basis calculated at one market location is found to lead the basis at another market location, then this suggests that the leading market plays a role in determining the basis for the other market. The findings suggest that corn basis calculated at the export terminal markets of Toledo and the U.S. Gulf, as well as the Illinois River, may indeed provide valuable information in determining the basis for other river terminal and interior locations.