Today, Forbes released its list of the 100 most powerful women on Earth. It includes prime ministers, pop stars, media moguls and a woman who declared war on the muffin top and won. The founder of... See More
Today, Forbes released its list of the 100 most powerful women on Earth. It includes prime ministers, pop stars, media moguls and a woman who declared war on the muffin top and won. The founder of span. She is 43, and the world's youngest female self-made billionaire. Tonight she takes my "Nightline" co-anchor juju Chang directly inside the dressing room. ? Red carpet secrets? Spanx. Spanx. Reporter: The not so secret secret to looking slim and trim. You have got to wear spanx. Reporter: That must-have undergarment, celebrities can't stop blabbing about. Spanx. Reporter: With an empire built on undergarments, spanx inventer and founder Sarah Blakely has reached the holy grail. Making "Forbes" magazine's list of the worlds 100 most powerful women of 2014. This is our active wear. I am excited about. Reporter: What started as a simple idea. A fresh take on the old girdle has exploded into a billion dollar brand name. Spanx has revolutionized the way women get dressed. It's hard for me to absorb, that's a product I created. You know? I created that. Reporter: Spanx now sucks in $250 million in annual sales. With not one penny of advertising. What we hear the most from e-mails and phone calls is confidence. I feel confidence that I don't have normally. I mean just -- it is a really great feeling. Reporter: Spanx expanded to more than 200 products sold in 13 countries. Spanx! Spanx! Reporter: To offer her royal lady a unique shopping experience -- Come on in, ladies. We are open. Blakely opened up spanx stand-alone boutiques, expanding her empire. Beyond just cinching it in. Reporter: Should Victoria's secret be worried? I would say so. Where do you put that in your head? I think I mostly giggle when I think about it. It remind me of those backdrop, you would choose at the mall with your friends. You know like, like I'm -- I'm the sexiest woman alive. Yeah. Reporter: In addition to control tops she is taking on a new set of curves. Everything from yoga pants, swim suits, even bras. I'm wearing one now. It's become one of my favorite products. The bra. Bring it up to speed. Get red of Ba-- rid of back pat. Pantyhose T wires, clasps free. Airport friendly. Reporter: Her mammoth success had humble beginnings in Clearwater, Florida. I was always frying to find ways to make money and businesses. My first memory is drawing pictures with of my friend on a rainy day and selling them door to door. Reporter: But her life's biggest pivot point was traumatic on a bike ride she witnessed her best friend get hit and killed by a car. In her grief she turned to self-help tapes. I memorized all ten tapes of Wayne dyer's how to be a no limit person. I feel that that really changed the trajectory of my life. Reporter: The tapes helped her cope with failure and rejection when she bombed the exam to get into law school. She spent seven years selling fax machines door to door. Sometimes people would be particularly nasty and rip up my business card in my face. I would sit in the car and cry and put in some sort of motivational tapes and just usually shift my thinking. Reporter: Then she had that ah-ha moment that would forever change her life. Sparked by a troublesome pair of cream colored pants. Every time I put them on you could see the thong, see the panty line, see cellulite on the back of my thighs, I cut the feet out of control top pantyhose one time. My rear looked firm. It had been smoothed out. I knew that that was the idea I had been asking for. Reporter: With $5,000 in savings she started cold calling hosiery mills. One guy called and said I decided to make your crazy idea. And he ran it over the daughters at dinner. They said help her make it. A great idea with a catchy name. Reporter: Why spanx? I knew it was right. My product was about the butt. What was the runner-up? Open toed Delilah's. As luck would have it two months into business, Oprah anointed spanx footless pantyhose one of her favorite things of 2000. I love spanx. I love spanx. The rocket had been ignited from a one woman business to a shape wear empire in a decade. I fast forward all these years late tire stand in front of my store. An emotional moment. Her husband says she is a business titan because she listens to her intuition. She didn't go to Harvard business school. Trusts her gut. Entered a male dominated space with no business experience and said I will go for it. Blashe wants to launch women entrepreneurs. It's my way to pay the Oprah moment forward. This is a girl, Lindsay Phillip, invented a flip-flop. Switch flops. The key to Blakely's success is taking the lightbulb moment and keeping it glowing. If you are in search of your idea. Put on your awareness glasses. Look at things differently. There are million dollar idea everywhere. Reporter: For "Nightline," I'm juju Chang in New York.
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