Soil enzymes are important components of soil quality because of their involvement in ecosystem services related to nutrient cycling, global C dynamics and soil detoxification. This symposium will provide an overview of the history of soil enzymology and development and utilization of soil enzyme assays and of innovative molecular approaches. This symposium is organized in honor of Professor Tabatabai, a long-term SSSA member and internationally recognized for his important contributions to soil enzymology at Iowa State University.