Using an "engaged approach," this valuable resource offers a clear, easy-to-follow presentation of the basic mathematical components, ethics, and study design options in epidemiology, as well as the primary types and sources of error in epidemiologic studies. It covers key issues associated with solving public health problems, from a solid understanding of fundamental principles to the methodologies employed by epidemiologists or other public health professionals. Its unique global perspective includes discussions of emerging and re-emerging diseases.