The Third Edition of this popular text continues to provide students with a clear view of the complex modern U.S. public health system-what it is, what it does, how it works, and why it is important. Using a straightforward systems approach, this text will give your students a solid grounding in the essential concepts of public health, and the relationship of public health to the health care delivery system as a whole.Public Health: What It is and How It Works presents a uniquely comprehensible framework for understanding the inner workings of public health by examining:- The origins and development of the modern public health system.- The relationship of public health to the overall health system and its intervention strategies.- How the U.S. public health system is organized at the federal, state, and local levels.- Its core functions, how, and how well these are currently being addressed.- Evidence-based public health practice and an approach to program planning and evaluation for public health interventions.- Public health activities, such as epidemiological investigations, biomedical research, environmental assessment, policy development, and more.