Desmond Tutu. The first black Archbishop of Cape Town, Tutu has won the Nobel Peace Prize for his leadership of the South African Truth and Reconciliation Commission and today is Chair of a group of former world leaders, The Elders, which aims to tackle some of the world's most intractable problems.

He has helped calm the political crisis in Kenya and regularly speaks out against Mugabe, Israel, the Iraq War and the Burmese junta, but is also noted for his irrepressible sense of humour and deep spirituality. He lives in South Africa but travels widely.

Born in Montreal in 1970, Naomi Klein is an award-winning journalist and author of the international bestseller No Logo, which was shortlisted for the Guardian first book award. Translated into twenty-five languages, No Logo was called "a movement bible" and placed Naomi Klein at the vanguard of a new wave of considering globalisation and corporations.

In Blank is Beautiful, Klein will once again revolutionize our way of thinking. Naomi Klein writes an internationally syndicated column for the Guardian and her articles appear in numerous publications, including The Nation, The New Statesman, Newsweek International, the New York Times and the Village Voice.

A collection of her work, titled Fences and Windows: Dispatches from the Front Lines of the Globalization Debate, was published in October 2002. For the past six years, Klein has travelled throughout North America, Asia, Latin America and Europe, tracking the rise of anticorporate activism. She is a frequent media commentator and university guest lecturer and was a Miliband Fellow at the London School of Economics. Her latest book is The Shock Doctrine: The Rise of Disaster Capitalism (Penguin, 2007).