Mention Dale Carnegie or his best-selling book, How to Win Friends and Influence People, to your colleagues and you're likely to encounter cringes and knowing, semi-sarcastic smiles.

Perhaps it's the general ambience that surrounds Carnegie today, evoking images of Babbittry, good-natured guffaws and glad-handing, the perpetual American boosterism, that provokes these reactions.

Would you, for instance, still feel at peace earnestly reading "Six ways to make people like you," and "How to win people to your way of thinking," or, better yet: "How to change people without giving offense or arousing resentment?" Those ideas, each a section of Carnegie's How to Win Friends, seem to encourage us to apply a business method to our human relationships while simultaneously contributing cheerfully to the humming engines of capitalism.

So maybe I can be excused for arriving at the Yale Club in New York City in a somewhat snarky mood for the 100th anniversary observances of Carnegie's training method earlier this week. But that sentiment was soon swept away by the intelligence, old-fashioned niceness, and pleasant humor of Carnegie's current stewards.

"There is something very universal about what we do," Peter V. Handal, the chairman and chief executive of Dale Carnegie Training, said to the 15 or so people gathered around an enormous banquet table.

On October 23, 1912, Carnegie, who had been a poor farm boy from Missouri, began teaching his concepts to a class of nine people, primarily engineers, at the Harlem YMCA in New York City. Since then, eight million people have taken his training courses in 83 countries and in 30 languages. Actually, 60% of DCT's training revenues occur overseas today, Handal said.

Among the better-known graduates are Walmart founder Sam Walton, Berkshire Hathaway's Warren Buffet, Speaker of the House John Boehner, and President Lyndon B. Johnson.

But what, if anything, can entrepreneurs learn from Carnegie's methods today?

Well, it turns out the most critical problem Carnegie attempted to deal with--management of people in a business context--has certainly not been eradicated. Nearly half of all employees describe themselves as only partially engaged with their jobs, according to a study conducted in May of 1,500 employees nationwide by DCT and the metrics firm MSW Research, which is based in Lake Success, New York. Fewer than one-third of employees describe themselves as fully engaged with their work.

Employees care more about the quality of their work when they have a good relationship with an immediate supervisor, believe in senior leadership, and take pride in working for the company, according to the study.

David Fagiano, chief operating officer of DCT, put it another way. Most management problems can be solved if you attend to Carnegie's Golden Rule: Do Unto Others. 

While that may sound a bit biblical, it's tied to some more modern truths Carnegie understood, such as that you can't really change people, but you can change your own reaction to them. And just as important, that people hate overt criticism.

"Ninety-nine times out of a hundred, people don't criticize themselves for anything, no matter how wrong," Carnegie wrote in How to Win Friends, which was first published in 1936.

The book's influence is still widespread--you can find echoes of it in nearly every business publication. For example, take a Tuesday article on the Harvard Business Review website, written by Alan C. Wurtzel--son of  Circuit City founder Sam Wurtzel. The younger Wurtzel describes his father's captivation with a book from 1960 called The Human Side of Enterprse, by MIT professor Douglas McGregor. Its chief tenet: management succeeds only with the efforts of other people, so it's important to treat employees with respect and to give them opportunities to grow. These are Carnegian principles Wurtzel says his father practiced while building his business.

Similarly, Fagiano relayed a story of working recently with a company that produced gaskets for Toyota in Sheffield, England. The company allegedly had an abysmal record with defective products that didn't fit inside cars correctly, until management interceded to teach its floor laborers some of the Carnegie basics.

"We worked on team-building and responsibility, respect for each other and their work, and understanding where the other person is coming from, and it had nothing to do with the rubber being used to create the gasket," Fagiano said.

The defective product rate soon dropped to a fractional amount, Fagiano said.

That's not to say DCT hasn't updated its image in recent years. It has developed customizable management programs for businesses with specific problems, for instance. It's also adopted digital delivery of material and the use of Webinars. It even updated Carnegie's book in 2011. Yup, you probably guessed it: How to Win Friends and Influence People in the Digital Age.

Although the technology around us has changed, Handal said, Carnegie's most basic principles can still be summed up this way: Smile, think in terms of other people's interests, and engage in a friendly way.

That's advice that never goes out of style.