Podcast: John Barrasso
The Wyoming senator will never forget Kennedy's inaugural address.
Podcast: Regina Benjamin
The surgeon general talks about the broad federal fight.
Podcast: Warren Bennis
Freedom and the spirit of inquiry are U.S. strengths.
Podcast: Carol Browner
Climate czar says businesses need clear energy standards to compete in the global market.
Podcast: Anna Burger
The SEIU secretary-treasurer says unions must help level the playing field.
Podcast: Francis Collins
New challenges at the NIH include finding the genes that cause cancer, heart disease.
Podcast: Toby Cosgrove
Pioneering heart surgeon says failure is bad only if you don't recover from it.
Podcast: Cheryl Dorsey
Their blend of passion and pragmatism helps bridge ideological divides and speed change.
Podcast: Arne Duncan
Economic crisis poses a test of leadership for the nation's educators.
Podcast: John Hickenlooper
Climate skeptics should embrace efforts to mitigate global warming as an economic benefit.
Podcast: Tim Kaine
DNC chairman says Americans chose his party's confident and optimistic governing.
Podcast: John Kerry
Personal persuasion, taking the initiative, and spreading the hurt are deal-making skills.
Podcast: Bill McKibben
Author and environmentalist says individuals can help end dependence on fossil fuels.
Podcast: Grover Norquist
Leading conservative activist launched Taxpayer Protection Pledge.
Podcast: Diane Ravitch
The historian talks about what's gone wrong with American schools.
Podcast: Alice Rivlin
The former budget chief says debt is largely attributable to costs of an aging population.
Podcast: Maria Zuber
The female space pioneer talks about the importance of innovation.
Commentary: Michelle Obama
Having good teachers in classrooms is critical because education is the road to opportunity.
Commentary: David Gergen
Obama fired the imagination of the country during his campaign, but the glow has faded.
Commentary: Barbara Kellerman
Americans have always been reluctant to grant anyone the right to tell us what to do.
Get to know more about each person who made this year's list.
PHOTO CREDITS: Ben Bernanke: Charlie Archambault for USN&WR; Cory Booker: Jonathan Ernst/Reuters; John Chambers: David McNew/Getty; Yvan Chouinard: Matt Slaby/Luceo for USN&WR; John Doerr: Jim Young/Reuters; Cheryl Dorsey: Tony Deifell; Eve Ensler: Ulf Andersen/Getty; Norman Francis: Bill Haber/AP; Orrin Hatch: Brett Ziegler for USN&WR; Susan Hockfield: Josh Reynolds/AP; Ted Kennedy: Jim Lo Scalzo for USN&WR; Bill & Kathy Magee: Jeffrey MacMillan for USN&WR; Greg Mortenson: Courtesy Central Asia Institute; Ray Odierno: Charles Dharapak/AP; Eboo Patel: Nubar Alexanian; Sally Ride: Pablo Martinez Monsivais/AP; David Robinson: Jim Rogash/Getty; Judith Rodin: Ramin Talaie/Corbis; Senior Noncommissioned Officers: David Furst/AFP; Jim Sinegal: Jeffrey MacMillan for USN&WR; Twyla Tharp: Brendan Hoffman/Getty