Now in its fourth year, World Challenge 08 is a global competition aimed at finding projects or small businesses from around the world that have shown enterprise and innovation at a grass roots level. We would love to hear from our audience about social entrepreneurs who are making a difference without costing the earth. It could be you or someone you know.

World Challenge 08 is brought to you by BBC World News and Newsweek, in association with Shell, and is about championing and rewarding projects and business which really make a difference. The winner will receive a grant of USD $20 000 to put back into their project/business, and two runners up will each receive USD $10 000. One representative from each of the three finalists will be flown to The Hague, The Netherlands to attend the award ceremony in December 2008.