The 2008 financial crisis roiled the banking system and swamped the global economy, leaving millions of Americans jobless, underemployed or facing foreclosure. In its wake, Congress set out to overhaul how the government oversees Wall Street. The result was a sprawling law, the Dodd-Frank Act, which aims to prevent future crises by giving the government new tools and restricting banks' activities. The law may make future crises less likely, but it increases costs for companies, especially banks, and their customers.