A cooperative program between the Wisconsin Department of Natural Resources and the University of Wisconsin–Madison (UW-MSN) has resulted in the assessment of the trophic condition of approximately 3,000 significant inland lakes in Wisconsin. A sophisticated set of computer programs has been developed by the UW-MSN that locates the lakes that are to be classified, extracts the spectral reflectance values from Landsat digital data for those lakes, and then adjusts the lake data for atmospheric effects. The corrected lake statistics from Landsat data are correlated to measured field parameters collected on a limited number of lakes. Finally, the relationships developed are used to predict the trophic condition of the significant lakes in the State.