The complexities and contradictions associated with trophic classification criteria are discussed in this report. Many criteria are based on the process of nutrient enrichment (i.e., eutrophication) while others are based on the manifestations of eutrophication. Numerous chemical, physical, and biological criteria are compared within a tabular format. As presently used, trophic classification of lakes and reservoirs becomes a function of the criteria used and is frequently inconsistent among classification criteria. A more practical approach to lake classification would place paramount consideration upon the potential beneficial uses of a lake and the water quality characteristics required to meet those uses. (Author)