At the end of this month, four billion people around the world will watch the televised opening ceremonies of the 2012 Summer Olympics in London. More than 10,000 athletes from more than 200 countries will compete, all hoping to be the fastest, strongest and best in their fields. Britain will spend about $19 billion on the event at a time when a financial crisis is raging across Europe and governments are slashing spending. While the sports-loving British are mostly enthusiastic about hosting the event, some question whether so much money should have been spent on non-essential sports facilities during a time of austerity and whether the city will ever get a return on its massive investment. Athens, the last European capital to host the summer games, incurred a huge debt that it may never be able to repay. Yet cities around the world -- even in developing countries -- continue to vie fiercely for a chance to host the games. But what do cities hope to gain from the event, and what are the real costs involved?

Christopher Hack is a London-based freelance writer and economic analyst working for The Economist Intelligence Unit and The Observer and Guardian newspapers, among others. He writes on contemporary events in Britain and Europe and is a former foreign correspondent in Beirut, Lebanon, for the BBC and Time. He earned a Joint Honors degree in politics and economics in 1993 at the University of London.