Money laundering says the process of concealing the source of legally, illegally, and grey area obtained monies.
The methods by which money may be laundered are varied & can range in sophistication. Many regulatory & governmental authorities quote estimates each year for the amount of money laundered, either worldwide (or) within their national economy. In 1996, the International Monetary Fund estimated that 2 to 5% of the worldwide global economy involved laundered money. However, the Financial Action Task Force(FATF) on Money Laundering(ML), an intergovernmental body set up to combat money laundering, admitted that "overall it is absolutely impossible to produce a reliable estimate of the amount of money laundered & therefore the FATF does not publish any figures in this regard".
Regardless of the difficulty in measurement, the amount of money laundered each year is in the billions (IN US dollars$) & poses a significant policy concern for governments. As a result, governments & international bodies have undertaken efforts to deter, prevent & apprehend money launderers. Financial institutions have likewise undertaken efforts to prevent & detect transactions involving dirty money, both as a result of government requirements & to avoid the reputational risk involved.