Mounting concern for the state of the environment has led to a substantial increase in the collection of environmental data in the past two decades. This trend raises issues with regard to the quality assurance and quality control of the data gathering process, from sampling to analysis. The evaluation of environmental data in terms of quality, and relevance for use in the management of toxic chemicals in the enviroment, has reached a critical phase. An enormous volume of data is being generated, on both residue levels and their effects, to meet short- and long-term needs for regulatory procedures and (environmental) impact assessments. Therefore, it is important to verify not only the quality of the data collected, but also the choice of relevant test parameters. This volume deals with the evolution of analytical methodologies to the current state-of-the-art techniques, quality assurance/quality control of data acquirements, and testing procedures for screening of toxic chemicals - including their hazard identification, persistence, and fate processes in the environment. The models currently employed in environmental impact assessment and risk assessment are also discussed in detail. Public involvement and participation in regulatory decision-making processess is also described. It is intended for managers and scientists involved in environmental management and research of toxic chemicals in the environment.