Several issues prompted regional discussions regarding N use rates for corn across the Midwest USA.  These included variation in systems between states, differences in methods for determining recommended rates, high N fertilizer prices, and mounting research evidence that high yield expectations clearly overestimate N fertilization needs using yield-based systems.  An outcome of the discussions was a new approach to N rate guidelines that is applicable on a regional basis.  The underlying principle for the regional approach is to have rate guidelines based directly from results of recent N rate response trials.  Databases of response trials represent a population of potential corn yield responses to N, and analysis of that data for economic net return directly provides the rate guidelines.  The key process is calculation of net return for individual trials using regression models based on yields for each trial.  The point of maximum return to N (MRTN) across a specific dataset is the most profitable and suggested rate, and returns near the MRTN define an N rate range that provides similar profitability.  The regional approach is described in a multi-state extension publication (“Concepts and Rationale for Regional Nitrogen Rate Guidelines for Corn”), and a web site (“Corn N Rate Calculator”) allows users to determine rates directly from the databases for different rotations and geographic regions.  The databases were queried for factors that may influence N response and no basis was found for separation based on tillage or yield level.  The approach is currently implemented in five states; Iowa, Illinois, Minnesota, Wisconsin, and Ohio.  An important aspect of the approach is the ability to easily revise the N response trial databases, which immediately updates suggested N rates.  This approach can be used for corn in any rotation.  The only requirement is having an adequate set of N response trials.