Development of realistic lake resource management strategies that have utility across diverse geopolitical areas is undoubtedly a difficult task. A regional approach, the aquatic ecoregion approach, is employed to examine spatial patterns in ambient phosphorus (TP) levels, secchi disk transparency, and lake morphometry. This approach defined seven distinct ecoregions, four of which were in Minnesota. For Minnesota, the analysis indicates that no single TP concentration can be used as a basis for setting standards across Minnesota because of its tremendous diversity of lakes. Potential lake management schemes are proposed based on this analysis.