FLASHBACK: Oprah Winfrey Launches 'O Magazine' in 2000 With Star-Studded Affair

It's been 15 years since Oprah Winfrey first launched O Magazine back in 2000. It was her first venture into the world of publishing and ET has been there from the very beginning.

"The magazine is called O because it is my vision, it is my ideas, what I have learned over the years," the media mogul told ET. "You know, I've done a lot of talking."

WATCH: 'O Magazine' Turns 15! Here Are The 7 Most Important Covers

Her vision was clear: to provide women a guide to lead better lives. An extension of her own voice, Oprah hoped readers could find themselves in stories about other people, a mission she shared for so many years with The Oprah Winfrey Show.

"Everybody is looking for a way to say, 'You know, I'm really OK,'" she said. "This magazine for me is a way of validating that and helping woman to see that for themselves."

ET joined Lady O at the 2000 launch party, along with a few of her several famous friends including Rosie O'Donnell, Barbara Walters, Diane Sawyer, Maria Shriver and fellow lifestyle guru Martha Stewart who had few words of advice for Oprah. "Putting out a magazine is hard but Oprah has done a lot more than I have," she quipped.

WATCH: Oprah Shares Life Lessons in 'What I Know For Sure' 

The following year O Magazine celebrated its one-year anniversary in publication. While it came as no surprise to the rest of us, Oprah was elated that the magazine had become a smashing success in its inaugural year.

"It resonates as a good thing," she told ET at the one-year anniversary party. "We had an idea and it worked!"

Over the years we've been behind the scenes for nearly every hairdo, doggy photo shoot and 'favorite thing' since the magazine's inception. Watch the full video for a special look back at O's most memorable cover shoots.

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