An authoritative, accessible guide to how our lungs work and how to protect them. Every day, our lungs circulate 11,000 liters of air, provide us with life-sustaining oxygen, and allow us to speak, sing, and smell. It's no secret that our lungs are one of our most vital organs, and yet most of us pay them little attention. The Covid-19 pandemic, however, has reminded us of the importance of our lungs, and sparked interest in their function and the risks they face. In breathing lessons, leading pulmonologist and national spokesperson for the American Lung Association Dr. MeiLan K. Han takes readers on a fascinating tour of this neglected yet crucial organ. Han explains the wonder of breathing and reveals how the lungs serve as the body's first line of defense. She provides a timely overview of the latest scientific thinking about the leading respiratory risks-including indoor and outdoor pollution, smoking and vaping, wildfire smoke, and viruses like Sars-CoV-2 and offers practical advice on how to protect the lungs at each stage of our lives, beginning in the womb. She outlines the major categories of chronic lung disease and demystifies the process lung doctors go through in making a diagnosis and recommending treatments. With authority as both practitioner and medical researcher, Han argues powerfully for social policies that make preserving lung health a national priority.