Dale Carnegie (1888–1955) was an American writer, lecturer, and adult education teacher whose 1936 book How to Win Friends and Influence People invented the self-improvement genre as it exists today. Before the book, "improving yourself" meant table manners or appreciation for fine art — not interpersonal skill. Carnegie was the first to argue systematically that the ability to deal with people is both the highest-value skill in professional life and something that can be deliberately learned.
Carnegie grew up on a Missouri farm and spent his early career giving public speaking courses to business adults in New York, eventually at the Engineers' Club of Philadelphia and the American Institute of Electrical Engineers. More than 1,500 engineers passed through his classes — they came because they had realized the highest-paid personnel in engineering are rarely the most technically skilled, but those who can lead and inspire people. That observation became the spine of everything he taught.
The book grew from fifteen years of lectures, field-tested on thousands of adults who then reported back which techniques actually worked. Carnegie claimed he didn't write it — he "collected it." The research included hundreds of biographies, newspaper archives, philosophical texts, psychological literature, and personal interviews with Edison, Marconi, Franklin Roosevelt, Clark Gable, Helen Keller, and dozens of others.
He was not the model of perfect human relations he described. He kept a file he called "Damn Fool Things I've Done" and admitted he violated his own principles constantly. The book was written partly for himself. His daughter Donna recalled a family friend dropping by just after her parents had argued, seeing Carnegie still fuming, and saying: "There goes the man who wrote the book."
The Dale Carnegie Training organization he founded continues to operate worldwide. The book has sold over 30 million copies and been translated into almost every major language.