Tony Juniper is an independent sustainability and environment adviser, and a Senior Associate with the Cambridge University Program for Sustainability Leadership. He advises international companies and speaks and writes on many aspects of sustainability. He is the author of several books, including the award-winning Parrots of the World, Spix's Macaw and How Many Light Bulbs Does It Take To Change A Planet? He writes a weekly Green column for the Sunday Times home section and is the editor of the new National Geographic Green supplement. He began his career as an ornithologist, working with Birdlife International. From 1990 he worked at Friends of the Earth and was the organization's executive director from 2003-2008.