30 years later, Trump's 1987 book 'The Art of the Deal' still says a lot about the way he views leadership

Though Trump's ghostwriter, now-HR-consultant Tony Schwartz, has since renounced his ties to the president, there are clear elements of "The Art of the Deal" that Trump continues to use as talking points.

The book shows how his career as a real estate developer in the '70s and '80s created his approach to business and leadership, including why, in his campaign, he would portray his deal-making in New York City as a miniature version of how he would approach the US.

While there is still much to learn about Trump's management style as president of the United States, the highlights he chose from his early career offer some insight into his approach to making deals.