Over the next several years, Carnegie developed his teaching style and began to see that he was making the most profound impact on business professionals. While technical ability helped his students to be successful, he realized that it was people skills -- social and communication -- that mattered most. He wanted to teach people to think on their feet in a public setting and to gather self-esteem from these teachings. Another revelation came to him around this time: there were no textbooks for these subjects, so he set out to research for what would eventually become his bestseller "How to Win Friends and Influence People".
“Dealing with people is probably the biggest problem you face.”
The book sold more than 10 million copies and was published in many different languages. This success of the book boosted Carnegie's speaking career and created demand for further self-help, social skills-driven books -- from him and others. (source: Famous Authors)
After the resounding success of his book, Carnegie founded the Dale Carnegie Institute for Effective Speaking and Human Relations, to teach public speaking skills to business professionals. During his lifetime, the institute expanded to 750 cities in American cities and was in 15 countries around the world. By the time of his death, 450,000 people had taken his classes. While lecturing at a prolific rate, he also found time to write several biographies about people he admired, including one on Abraham Lincoln. He also wrote another self-help book to critical acclaim -- "How to Stop Worrying and Start Living", in 1948. (source: Biography)
Years after divorcing his first wife, Carnegie went on to marry Dorothy Price Vanderpool in 1944. At the time he jokingly said, "Even after I wrote that book, it took me eight years to influence a woman to marry me." Vanderpool was instrumental in helping him grow the institute and, interestingly, creating classes for an emerging class of young professional women (due, in part, to World War II). She founded the Dorothy Carnegie Course in Personal Development for Women in 1945 which existed until the mid-1960s. The couple had a child in 1951 when Carnegie was 63. Four years later, his health would falter and on November 1, 1955, Carnegie died from uremia. Just before his death, he summed up what he had learned over his storied teaching career:
"Learning isn't so important, it's what kind of man (or woman) you make out of yourself while you're learning that counts."