Living in an urban environment can have a major influence - both positive and negative - on one's physical, psychological, and social health and well-being. According to recent statistics, 80.7% of Americans and more than half of the world's population live in cities. This book examines key issues related to city living and what's being done to address them, from pollution and crime to overcrowding and more. Includes city case studies and expert interviews in a variety of fields.