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Angela Merkel, Chancellor, Germany\n\nGerman Chancellor Angela Merkel's top billing derives in part from her leadership of the EU's biggest and most competitive economy, and for her crucial role in negotiations over euro zone sovereign debt.\n\nKnown as 'the decider', nothing gets done in Brussels without her consent. Despite a tough two years for the EU, Merkel's calm handling of negotiations have sent her stock at home soaring; last month her approval rating in Germany reached 77 percent. (Bloomberg)
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Dilma Rousseff, President, Brazil\n\nDilma Rousseff had some pretty big shoes to step into when she was elected president of Brazil in 2010. Predecessor Luis Inacio Lula Da Silva is regarded as the most popular politician in the country's history and was credited with its remarkable turnaround. While Brazil's economy has suffered as a result of the global crisis, Rousseff seems to be finally getting control of her wayward cabinet, while popularity at home is still high.
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Hillary Clinton, Secretary of State, US\n\nThe most globe-trotting member of the US government. Secretary of State Hillary Clinton is a regular visitor to the Gulf. Heading up a department that dictates American foreign policy, Clinton is President Obama's most influential advisor on matters outside the US. Don't bet against her running - and winning - the presidency in 2016. (Getty Images)
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Christine Lagarde, Managing Director, International Monetary Fund\n\nParachuted into the IMF after former managing director Dominique Strauss-Kahn's embarassing indiscretions in a New York hotel, Christine Lagarde took the helm at one of the crucial points of the agency's history. She will now direct the IMF as it seeks to provide advice and funds to countries attempting to move out of the global financial crisis. Lagarde previously served as French finance minister and the minister for commerce and industry. (AFP/Getty Images)
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Michelle Obama (left), wife of US President Barack Obama\n\nWhereas most first ladies have tended to keep a low profile, Michelle Obama has been the exception. She has used her position to become a role model for women and has also become an advocate for poverty awareness, nutrition and healthy eating, spearheading a US childhood anti-obesity campaign. (AFP/Getty Images)
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Indra Nooyi, Chairman and CEO, PepsiCo\n\nThere's no lack of powerful Indian women in the world; Sonia Ghandi and Pratibha Patil just missed out on this list. But we rated Indra Nooyi as the most powerful businesswoman in the world, due to her position as chairman and CEO of PepsiCo, the second largest food and beverage conglomerate on the planet. (Getty Images)
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Julia Gillard, Prime Minister, Australia\n\nAustralia has been the surprise of the financial crisis; the economy has ridden out the storm pretty well Down Under. Julia Gillard took over the top job in June 2010, becoming Australia's first female leader. (Getty Images)
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Queen Rania, Queen of Jordan\n\nThe wife of King Abdullah of Jordan, Queen Rania has used her position to champion education and health programmes in her own country. On the global front, she has been particularly supportive of interfaith dialogue.
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Aung San Suu Kyi, politican, Myanmar\n\nAfter 15 years under house arrest, Nobel Peace Prize laureate Aung San Suu Kyi was finally released in November 2010. During her time in captivity, she campaigned tirelessly for a non-violent solution to the military dictatorship ruling the country. In January, Suu Kyi announced that she would compete for a parliamentary seat in April's elections.
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Christina Kirchner, President, Argentina\n\nHead of Latin America's second-largest economy, Christina Kirchner has just won a second term as Argentina's president. She is a notable advocate for human rights, poverty awareness and healthcare issues. (Getty Images)