It reviews the history of this science and discusses the principles of toxicant action and disposition as well as the pathology of poisoning. Analytical principles of the field are also described. The text discusses the coroner and medical examiner system along with the toxicologist's responsibilities regarding case investigation, evidence collection and storage, quality assurance and proficiency testing, and substance analysis. Staff of the forensic laboratory are identified, and the lab's design is described. Analytical findings with frequently encountered psychoactive and peripherally acting drugs are discussed. The text also covers methods of giving expert testimony in court, ways to interpret toxicological data, data reporting and collection techniques, the private practitioner's role, and the activities of professional organizations and boards. Academic training programs in the field are also described, and model curricula are suggested. Chapter references, data tables and charts, diagrams, an index, and photographs are supplied. For individual articles, see NCJ 89876-81.