Book excerpt: *Comprehensive discussion of environmental stressors affecting aquatic ecosystems and organisms *Contributions from leading scientists in the field *Practical manual for students and researchers on the use of biocriteria *A practical guide to the use of biocriteria for assessment of the effects of environmental stressors on aquatic ecosystems and organisms, especially fish. Written by scientists who are experts in their fields, this book provides helpful information for designing and applying bioindicators in the field to reliably assess the health of aquatic organisms and ecosystems. This volume may be used as a manual for scientists, students, and others, in a variety of disciplines and applications