The enforcement efforts reflect the realization that drug trafficking is cash-intensive and so lucrative that it may be best understood as simply a big business. However, cash is much more difficult to conceal than drugs, so it must either be smuggled out of the United States or placed in a bank to become usable. Therefore, drug money is mixed with "clean" money and transferred by wire through a series of banks, disguising the source of the cash. However, the 1988 law has broadened the definition of money laundering and increased the penalties. Photographs, diagrams, and descriptions of specific enforcement efforts and changes in money laundering techniques