Ashok Khosla is one of world's leading experts on the environment and sustainable development. A former director of the United Nations Environment Programme, he was awarded the 2002 Sasakawa Environment Prize - "the Nobel Prize of the environment world" - and has been named in the UNEP's Global 500 Roll of Honour.

Born in Kashmir in 1940, the son of a university professor and a college lecturer, Khosla gained a masters degree in natural sciences from Cambridge University before going on to do a PhD in experimental physics at Harvard.

After a period teaching in the United States - he was part of the team that designed and taught Harvard's inaugural undergraduate course on the environment - he returned to his native India where he became the founding director of the Indian government's Office of Environmental Planning and Co-Ordination, the first such agency in a developing country.

In 1976 he was appointed director of the UNEP, where he designed and launched Infoterra, the global environmental information exchange. He remained with the UNEP until 1982 when he left to found Development Alternatives, a Delhi-based Non-Governmental Organization devoted to promoting commercially viable, environmentally friendly technologies.

He has been a board member of numerous global environmental organizations - including the Club of Rome, the World Conservation Union and the International Institute for Sustainable Development - and served as an adviser to, among others, the World Bank, the United Nations Development Programme and the Indian government.

In his presentation speech for the Sasakawa Award Klaus Toepfler, Executive Director of the UNEP, described Khosla as "a legend in the realm of sustainable development, and an individual who personifies the hopes and dreams of billions trapped in the indignity of acute deprivation."

He lives in Delhi.