Tracy Kidder profiles Dr. Paul Farmer, who built an organization delivering high-quality healthcare in the poorest places on earth. Farmer, trained at Harvard Medical School and Harvard's anthropology department, founded Partners in Health to treat tuberculosis and later AIDS in Haiti's Central Plateau. Kidder traveled with Farmer, observing his grueling schedule—seeing patients, hiking to remote villages, flying between continents to raise money and advocate for the poor. The book examines Farmer's philosophy: that the poor deserve the same quality care as the wealthy, that lack of resources is no excuse for inferior treatment, that diseases of poverty are society's responsibility. Kidder also shows Farmer's contradictions and critics: his impatience, his difficulty delegating, questions about whether his approach can scale. But the overall portrait is of moral clarity put into practice. For readers interested in global health, social justice, or what one person's commitment can accomplish, this book provides both inspiration and concrete example.