The 2010 TIME 100

Graça Machel is a born freedom fighter. Long before she became one of the world's most effective — and joyful — advocates for the rights of children, women and refugees, she was a schoolteacher in Mozambique seeking her country's liberation from Portugal. In 1975, when it gained independence, she was named Minister for Education and Culture; she also married Samora Machel, who had become Mozambique's first President. He died in a plane crash 11 years later, and in 1998 she wedded Nelson Mandela. She remains the sturdy shoulder that the South African leans on.

Machel, 64, has a warm smile, a hearty laugh and a way of making everyone feel comfortable. She continues to campaign against pediatric AIDS and the abuse of children and refugees. Along with Mandela, she is a charter member of the Elders — an independent group of global leaders — but on her own, she remains a potent voice for justice, one that is always listened to.

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