THR's Women in Entertainment 2011: Power 100

In just two years, 25-year-old Stefani Germanotta, better known as pop superstar Lady Gaga, has accomplished what many in the music industry thought was impossible in the age of piracy: She sold albums -- 23 million of them worldwide. But success, which also includes some 64 million singles legally downloaded, didn't come solely as an outcome of quality music, honed in dingy clubs all over New York's Lower East Side and later produced by the likes of RedOne (Jennifer Lopez's "On the Floor"), Fernando Garibay (Enrique Iglesias) and Mutt Lange (Def Leppard, Shania Twain). It was in equal part Gaga's business savvy that catapulted the singer from lounge act to arena seller.

PHOTOS: THR's 2011 Women in Entertainment Power 100

Take, for starters, the Haus of Gaga, which harnesses the creative power of a team of loyalists who guide everything from Gaga's avant-garde style to the visual aesthetic of her music videos -- high-budget clips rolled out so regularly that she's rarely out of the public eye for more than a day. There's also Gaga the tireless traveler, who has circumnavigated the globe several times over touring in support of hit albums The Fame Monster and Born This Way. The tour for the former grossed $227 million after 18 months on the road and Born sold 1.1 million copies in the U.S. its first week out, thanks in large part to a promotion offering the album for 99 cents on Amazon (demand for the download ended up momentarily crashing the retailer's servers).

And who can discount the more than 16 million followers she's amassed since joining Twitter in 2008? Gaga gives back, too, as a vocal advocate of gay rights, a contributor to the fight against AIDS and an impassioned critic of bullying, and she sometimes will bring the cause to the red carpet, as she did at the 2010 MTV Video Music Awards, when she was escorted by four soldiers directly affected by "Don't Ask, Don't Tell."