THR's Women in Entertainment 2012: Power 100

Walsh, 45, has watched over several hundred of the country's top authors for the better part of two decades and is continually upping her game. Case in point: 2012 best-sellers by Bill O'Reilly (Killing Kennedy and Killing Lincoln); self-help smash The Tools by L.A.-based psychotherapists Phil Stutz and Barry Michels, which WME sold in 40 countries; the series What Do You Want to Do Before You Die?; and No. 1 best-seller Bringing Up Bébé, which addresses what French women are doing right about parenting (the New York-based Walsh has three children, ages 18, 14 and 10). With the recent WME addition of Tina Bennett from Janklow & Nesbit, authors Malcolm Gladwell, Laura Hillenbrand, Atul Gawande, Amy Chua, Lev Grossman and Eric Schlosser join the agency's roster. Walsh also can claim bragging rights to The Perks of Being a Wallflower, adapted from the 1999 novel by Stephen Chbosky, who also directed the movie, and Cameron Diaz's forthcoming book on fitness and diet aimed at young girls, due out in fall 2013.

What I'd tell my 22-year-old self about working in Hollywood: That very little is fatal. Everything felt so do-or-die for me at that age. One of the beauties of being 45 is that I've learned how to conspire toward life. It's about being effective and impactful and significant. Beating yourself up for mistakes is actually not very useful. Once you learn from it, you move on, that's it.

Top three shows on my DVR: Homeland, Real Housewives of New York City and The Voice, although I was obsessed beyond belief with Downton Abbey. I watched the entire series in four days. … It was like crack cocaine.

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