From authors Friis and Sellers comes the Fourth Edition of this best-selling introduction to epidemiology: Epidemiology for Public Health Practice. In clear and accessible language, this comprehensive text will introduce your students to the most important and timely issues in epidemiology today. New to this edition: Information on new disease outbreaks: *E. coli in spinach *Avian influenza *XDR TB * Expanded coverage of the history of epidemiology * New coverage of the natural history of disease * Updated coverage of morbidity and mortality data throughout the text * Method for rate adjustment updated to the 2000 standard population * New information on health disparities, including the * Hispanic mortality paradox * Updated information on data sources including notifiable diseases * Additional statistical measures provided, e.g., measures of life expectancy * New coverage of models of causality * New chapter on professional issues in epidemiology * Exciting new figures, tables, and exhibits provided throughout * Additional exercises and study questions