Hillary Diane Rodham Clinton is the 67th United States Secretary of State, serving in the administration of President Barack Obama.

She was a United States Senator for New York from 2001 to 2009. As the wife of the 42nd President of the United States, Bill Clinton, she was the First Lady of the United States from 1993 to 2001.

Graça Machel, DBE (born Graça Simbine; 17 October 1945) is a Mozambican politician, humanitarian and international advocate for women’s and children’s rights.

She is the third wife of former South African president Nelson Mandela and the widow of the late Mozambican president Samora Machel.

She is the only woman in the world to have served as the First Lady of two different nations.

Margaret Heffernan is an entrepreneur, Chief Executive and author. She was born in Texas, raised in Holland and educated at Cambridge University.

She worked in BBC Radio for five years where she wrote, directed, produced and commissioned dozens of documentaries and dramas.

Here are 14 provocative quotes from her TEDGlobal 2012 talk: