Megaprojects and Risk provides the first detailed examination of the phenomenon of megaprojects. It is an account of how the promoters of multibillion-dollar megaprojects systematically and self-servingly misinform parliaments, the public and the media in order to get projects approved and built. It shows, in unusual depth, how the Machiavellian formula for approval is an unhealthy cocktail of underestimated costs, overestimated revenues, undervalued environmental impacts and overvalued economic development effects. This results in projects that are extremely risky, with huge cost overruns and revenue failures, but where this is concealed from MPs, taxpayers and investors until it is too late. The authors not only explore the problems but also suggest practical solutions drawing on theory and hard, scientific evidence from the several hundred projects in twenty nations that illustrate the book.