This publication on Biological Data in Water Pollution Assessment: Quantitative and Statistical Analyses contains papers presented at a symposium held 20-21 June 1977 at Minneapolis, Minnesota. The symposium was sponsored by the American Society for Testing and Materials through its Committee D19 on Water in cooperation with The Center for Environmental Studies at Virginia Polytechnic Institute and State University. K. L. Dickson and John Cairns, Jr., Virginia Polytechnic Institute and State University, and R. J. Livingston, Florida State University, served as symposium cochairmen and editors of this publication.