The World 10 Most Powerful Women by Forbes.com

They are heads of state and first ladies, bankers and cultural icons, CEOs and entrepreneurial athletes. A fresh look at power and creative influence.

1-Michelle Obama

• Age: 46
• Title: First Lady
• Residence: Washington, DC
• Country of citizenship: United States
• Education: JD , Harvard University; LLM, Harvard University; BA/BS, Princeton University
• Marital Status: Married
• Children: 2
• She has made the office of First Lady her own. A forceful advocate of school nutrition standards and military families' affairs, she's more involved in policy than Laura Bush was. But unlike Hillary Clinton, who championed a secretive (and ultimately unsuccessful) health care reform, Obama has stayed away from hard policy. A fashion icon and an athletic mother of two, she's Jackie Kennedy with a law degree from Harvard and street sense from Chicago's South Side. She's also effective: In response to her Let's Move! campaign against childhood obesity, companies like Coca-Cola, Kellogg and General Mills have pledged to reduce the calorie content of their foods by 2012. The first lady remains popular: 54% of Americans view her favorably.

2-Irene Rosenfeld

• Age: 57
• Title: Chief Executive, Kraft Foods
• Residence: Kenilworth, IL
• Country of citizenship: United States
• Education: BA/BS , Cornell University; PHD, Cornell University; MS, Cornell University
• Marital Status: Married
• Children: 2

Her $26.3 million compensation package in 2009 made Rosenfeld the nation's second-highest-paid female, after Yahoo!'s Carol Bartz. She earned it, drawing fire early this year after announcing plans to acquire British candymaker Cadbury. Warren Buffett, whose Berkshire Hathaway owned 9.4% of Kraft, voted against the deal, calling it "dumb." When Rosenfeld refused to back down, Buffett retaliated by selling 33.1 million Kraft shares (one-third of Berkshire's stake). Who was right? Kraft's second-quarter revenues rose 25.3% to $12.3 billion, boosted largely by Cadbury's business in Europe and in developing markets. "Obviously I'm very pleased with the outcome," she says. On the home front, Kraft is spending more on ads to push core brands--Philadelphia Cream Cheese, Kraft Singles, Oreos and Mac & Cheese (her favorite).

3-Oprah Winfrey

• Age: 56
• Title: Talk show host and media mogul
• Source: television, self-made
• Residence: Chicago, IL
• Country of citizenship: United States
• Education: BA/BS , Tennessee State University
• Marital Status: Single

The world's most successful female media exec--she earned $1.35 billion over the last five years--is making some big changes for 2010-11. Her 25th season of Oprah, the program that has launched multiple careers, spawned countless bestsellers and helped millions of women feel that someone, at last, understands them, will air its final show on Sept. 9, 2011. Next up? Winfrey is launching OWN, the Oprah Winfrey Network, a joint venture of Discovery Channel and her own Harpo Productions, in January 2012. Among its offerings: Rosie O'Donnell back in the host's chair, Duchess of York Sarah Ferguson on a reality show and a new competition series produced by Survivor's Mark Burnett. Ending 2010 on an up note, she will be honored by the Kennedy Center in December for her 25 years in entertainment.

4-Angela Merkel

• Age: 56
• Title: Chancellor
• Country of citizenship: Germany
• Marital Status: Married

With a fragile coalition--and infighting between the FDP (liberals) and the Christian Social Union, with both of whom her party is allied--Merkel is trying to push through tax and education reforms before next spring's regional elections. With German business sentiment near all-time highs, she can afford to spend a little political capital. Germany's planned 4% cuts in the 2011 budget ($400 billion) may anger constituents, many of whom are looking for wage raises. Merkel is lobbying for a non-permanent seat for Germany on the U.N. Security Council; some believe she is angling for a permanent place.

5-Hillary Clinton

• Age: 62
• Title: Secretary of State
• Residence: Chappaqua , NY
• Country of citizenship: United States
• Education: BA/BS , Wellesley College; LLM, Yale University
• Marital Status: Married
• Children: 1

Diplomatic breakthroughs are rare. And while Clinton, a former first lady and U.S. senator, brings star power to the State Department, she has yet to notch a triumph beyond resetting the button in U.S.-Russian ties and the Turkey-Armenia treaty. She has put her skills on the line with an umpteenth attempt to broker Middle East peace. No one discounts her continuing contributions to the plight of women worldwide: victims of rape in Congo and of flooding in Pakistan and the millions of mothers exposed to dangerous cookstoves. What's next for Hillary? Heading up the World Bank--or becoming Obama's running mate in 2012?

6-Indra Nooyi

Age: 54

• Title: Chief Executive, PepsiCo
• Residence: Purchase, NY
• Country of citizenship: United States
• Education: MBA , Yale University
• Marital Status: Married
• Children: 2

This year Nooyi nudged a $20 million slice of the company's $616-million-a-year ad budget away from traditional to social media spends. A worldwide campaign, Pepsi Refresh, lets you submit grant proposals to a website, then encourages online voters to choose the winners (amounts: $5,000 to $250,000). "It blurs the line between philanthropy and advertising," says Nooyi, whose total annual compensation package last year was $10.6 million. Refresh also allocates $1.3 million each month for a U.S. project, such as the recent "Do Good For the Gulf," which offers stipends to build a shelter for animals whose owners lost their homes to the oil spill and to provide mental health services and job training. "Brands have to speak to millenniums; young people want to make a difference," she says.

7-Lady Gaga

• Age: 24
• Title: Singer and performance artist
• Residence: New York , NY
• Country of citizenship: United States
• Education: Dropout , New York University
• Marital Status: Single
• All hail the new queen of pop. Part singer and part performance artist, Lady Gaga (née Stefani Germanotta) has single-handedly reinvigorated pop music and pop culture. Her songs are like brain candy (sticky and addictive), her performances and fashion style are a spectacle. Her first album, The Fame, debuted in 2008, scoring four No. 1 hits with Just Dance, Love Game, Paparazzi and Poker Face. Her latest, The Fame Monster, has now put her on par with Beyoncé, Rihanna, and Mariah Carey for the most No. 1 Billboard hits (six) by a female artist. Her The Monster Ball world tour is poised to gross $200 million by the time it ends in May 2011. But it's not all pop and glamour for Gaga. She is vocal supporter of gay rights and the repeal of "don't ask, don't tell."

8-Gail Kelly

• Age: 54
• Title: Chief Executive, Westpac
• Country of citizenship: Australia
• Education: BA/BS , University of Cape Town
• Marital Status: Married

As head of Australia's second-largest bank, Westpac, with $551 billion in assets and $15.9 billion in revenue, and the country's most influential businesswoman, the native South African has an outsized public profile. Kelly's every statement and opinion--public or otherwise--is reported minutely, occasionally provoking national controversy. Since late 2009 Kelly has earned the ire of everyday Australians by drastically raising interest rates on loans. The problem, according to Kelly: Australian consumer savings rates are much lower than in other areas of the world, making it more expensive for banks like Westpac to seek out funding. She's hoping to attract more Australian savers this year to stop the vicious cycle.

9-Beyonce Knowles

• Age: 29
• Title: Singer, fashion designer
• Residence: New York , NY
• Country of citizenship: United States
• Marital Status: Married

Beyoncé had an income of $80 million last year, thanks to an ever-expanding artistic and business empire that includes 118 million records, seven films, 16 Grammy awards (she was the first woman to win six in one night) and numerous MTV Video Music Awards, including this year's collaboration with Lady Gaga, Telephone. Then there are the modeling contracts with L'Oréal and Coty, and a partnership in Deréon fashions with her mother, Tina. Her songs inspire everyone from Michelle Obama (Beyoncé's a go-to on the first lady's iPod) and the U.S. women's ice hockey team, who would warm up before Olympic games by dancing to her songs in the locker room. And the single ladies. A video of 7- to 9-year old girls dancing to the tune hit the Internet this year, creating a storm of criticism.

• 10-Ellen DeGeneres

• • Age: 52
  • Title: Talk show host
  • Residence: Beverly Hills , CA

  • Country of citizenship: United States
  • Marital Status: Married
  • If the title weren't already taken, it wouldn't be a stretch to call DeGeneres "queen of all media." Her eponymous chat show, a five-time Emmy winner, is now in its eighth season. She was an American Idol judge this year, but quit because, she says, it "didn't feel like the right fit for me." In between, she's a face for Cover Girl and Vitaminwater Zero and has been a runway model for designer Richie Rich. An outspoken gay-rights supporter, she came out in 1997 and married actress Portia de Rossi in 2008; de Rossi legally took DeGeneres' name last month. Putting her money where her heart is, this March the talk host gave a $30,000 college scholarship to Constance McMillen, a gay Mississippi teen who challenged her school's policy banning same-sex prom dates.