For 25 years, The Oprah Winfrey Show dominated television screens across America, reaching millions of viewers from 1986 to 2011.

She became a household name thanks to her iconic in-depth interviews with celebrities and regular people alike, diving into topics like addiction, infidelity, spirituality, polygamy, weight loss, racism, and so many more.

But after a quarter of a century, The Oprah Winfrey Show came to an end, partly because the staff was overworked — sometimes working 24 hours straight. It was out of fierce loyalty to Winfrey, with one producer saying she was a life-changing “mother figure” to the entire crew.

The staff also had a hard time coming up with fresh ideas and trying to disrupt themselves. Winfrey said, “It had become increasingly more difficult to top what you did the year before.”

The show’s end marked a new beginning for Winfrey. Since 2011, she has built a media empire. After studying Winfrey for weeks, I discovered something interesting: It’s rare for her to be the one being interviewed, and it’s even more rare for her to be interviewed about her business dealings.

Nevertheless, the biggest lesson I learned about Winfrey’s business philosophy is simple: Own everything. This allows you to be in control of your work, and write your own check.

Winfrey founded her own multimedia production company, Harpo Productions, and O, The Oprah Magazine. In 2011, Winfrey launched a cable channel, OWN, and her 25.5% stake in the network is worth more than $65 million. In 2015, she also bought a 10% stake in Weight Watchers (since lowered to 7%).

Winfrey says, “The reason I’ve been able to be so financially successful is my focus has never, ever for one minute been money.”

But don’t be fooled — Winfrey is methodical and strategic when it comes to growing her brand, allowing her to become a self-made billionaire. Forbes estimates Winfrey’s net worth at $2.5 billion.

The reason Winfrey’s success is so remarkable is that she wasn’t born into wealth or status of any kind. Born to a teen mom in Mississippi, Winfrey’s early life was fraught with poverty and abuse. She was raped by a cousin at age 9 and later sexually molested by a friend of the family and then by an uncle.

“It was this ongoing, continuous thing, so much so that I started to believe that this is just how life is,” she says. “I became a sexually promiscuous teenager, and as a result of that, got myself into a lot of trouble and believed I was responsible for it. It wasn’t until I was 36 years old — 36 — that I connected it all, ‘Oh that’s why I was that way.'”

The abuse happened when she was living with her mother, so Winfrey ran away from home, secretly pregnant at age 14. After she gave birth prematurely, the baby passed away two weeks later.

This was a pivotal, life-changing moment for a young Oprah.

Once she began living with her father, she got structure, discipline, and attention. “It changed the course of my life. He saved me,” she says. “He simply knew what he wanted and expected. He would take nothing less.”

And from then on, neither did Winfrey.

The Profile Dossier below details Winfrey’s rise from poverty in rural Mississippi to local talk-show host to global superstar. Here’s what we can learn about sharpening our interview skills, developing an entrepreneurial mindset, and building an empire.