Criminals who commit crimes that yield large amounts of cash must make the money appear to have come from legitimate activities, so that the money can be used without calling attention to the criminal's involvement in a criminal enterprise. Money laundering methods include transporting cash to countries where money laundering is easy to achieve; establishing a legitimate, cash-intensive business through which the money from a criminal enterprise can be funneled; or channeling the money through unwitting or cooperating legitimate financial institutions. In the latter case, Federal laws and their enforcement have been effective in gaining the cooperation of financial institutions in reporting suspicious cash transactions. Tracing the money trail constitutes the bulk of money laundering investigations. Investigations are prompted by tips received from Federal and State informants, the observation of drug dealers and others, and the routine review of Suspicious Activity Reports filed by financial institutions. The Financial Crimes Enforcement Network (FinCEN) establishes, oversees, and implements the U.S. Treasury Department's policies to prevent and detect money laundering. FinCEN provides analytical case support, through the use of state-of-the-art technology and intelligence analyses, to many Federal agencies as well as State and local law enforcement organizations.