The book "Small-scale Freshwater Toxicity Investigations" offers a comprehensive analysis of the challenges posed by the release of pollutants into aquatic ecosystems. It highlights the necessity of providing fundamental toxicological information to understand the effects of contaminants on living organisms. Given the multitude of published methods for toxicity testing and hazard assessment, the need for these procedures to be clearly documented and reproducible is emphasized. The work is aimed at professionals interested in the development and application of environmental programs for water quality preservation. It provides valuable insights into the standardization of testing methods and the importance of precise documentation to generate valid data and avoid misinterpretations. The authors, Christian Blaise and Jean-François Férard, contribute their expertise to guide readers through the complex subject of toxicity investigations.