The impetus for this book came from numerous requests by public and private agencies and citizens for information regarding the human health effects of pes ticide exposures. We have tried to compile a relatively complete, concise sum mary of the acute and chronic health effects and the toxicology of pesticides in a format that provides quick and easy access. This book was written to address the needs of the following groups: medical and public health professionals, tox icologists, environmentalists, industrial hygienists, regulators, producers and users of pesticides, public interest advocates, and the legal profession. Acknowledgments We are indebted to Mr. Christopher J. Wiant, Chief of the Environmental Chemistry Section of the Illinois Department of Public Health. The financial support provided by his office was essential in producing this book. We are also indebted to Dr. Charles Benbrook, former staff member, and Representative George E. Brown, Chairman of the Subcommittee on Depart ment Operations, Research and Foreign Agriculture of the Committee on Agri culture, United States House of Representatives, for their guidance in obtain ing pesticide toxicity data. In the Freedom of Information Office, Office of Pesticide Programs of the United States Environmental Protection Agency, the patience and assistance of Therese Murtagh and Virginia Salzman in obtaining documents are appreciated. Of the numerous individuals who participated in the production of this book, the following merit special recognition for the quality of their research, editing, and critical skills: Mark Loafman, Sue Ramirez, Steve Smith, Sally Burns, and Denise Steurer.