The new edition of this classic text continues its mission of describing the application of basic epidemiologic principles in real time, place, and person to solve problems of an urgent or emergency nature. Based on decades of experience in both infectious and noninfectious diseases at the Centers for Disease Control and Prevention, this book describes in clear and practical terms the distinct approach, tasks, and actions needed for successful field investigations. Guidance is given on such issues as how to perform surveillance, manage and execute field investigatins, collect and analyze data, perform surveys, adapt a personal computer for field use, and communicate the findings. Specific advice is also given on such subjects as dealing with the media; investigations in health care, day care, and international settings; and the legal aspects of field studies. An entire chapter covers the proper collection, handling, and testing of infectious and noninfectious agents in the field. This edition contains new chapters on environmental investigations and immunization practices for the field epidemiologist. The boko is based both on science and experience. It deals with real problems, real places, and real people: nature's experiment rather than carefully designed studies in a laboratory or clinical setting. So, in the lexicon of the epidemiologist, the book addresses issues relating to observational- not experimental- epidemiology.