All across the globe, experts are devising high-tech methods to combat counterfeiters. See which world currencies are most impervious to fraud and why in our gallery of bills
Anti-Counterfeiting Around the World:
In the United States alone, there's at least $70 million in fake currency floating around. Fortunately as the technology counterfeiters use improves, so does that of the bills. Color-changing ink, special polymers and holographs are just some of the innovative technologies incorporated into today's banknotes. In 2007, the International Association of Currency Affairs picked the best new counterfeiting technologies and tactics.