Money laundering is the process by which funds obtained through criminal activities are turned into funds that appear to have been obtained from one or more legitimate sources. The purposes of preventing money laundering are: 1) to maintain international financial order, as well as to establish law; 2) to secure financial soundness and transparency; 3) to prevent damage to financial institutions and to gain credibility; 4) to prevent social and national corruption; and 5) to block the negative impact of such criminal conduct on the national economy. How to perform money laundering ① Through casinos and racetracks ② Transactions in trade ③ Alternative remittance systems ④ Bank account, trust funds, bank loan, private banking, and bearer bond, etc. ⑤ Transactions on the stock exchange (brokerage account, investment trust) ⑥ Insurance ⑦ Financial derivatives ⑧ Electronic banking, electronic money The effort to prevent money laundering can violate the privacy of individual financial transactions. ⅰ. Suspicious Transaction Report (STR): The STR is a report that KoFUI (Financial Intelligence Unit of Korea) are required to file for any financial transaction that appears to a financial institution or its employee to be suspicious. The institution and the employee who implement an STR will be exempt from criminal and civil liability if there is no intentional error or mistake even though the report may turn out to be false. ⅱ. Currency Transaction Report (CTR): The CTR is a report that KoFIU are required to file for each deposit, withdrawal, exchange of currency, or other payment or transfer, by, through, or to the financial institution that involves a transaction in currency of more than $10,000 or 20,000,000 won. Unlike an STR, a CTR is compulsory. ⅲ. Customer Due Diligence (CDD): Regulations require that financial institutions identify their clients and ascertain relevant information pertinent to doing financial business with them to ensure securities transparency and soundness. A CDD is required for each one-time transaction involving more than 20,000,000 won or that may be related to money laundering. ⅳ. Establish a control system for each financial institution: An internal control system for each financial institution should enhance education and provide more information for employees and managers who are in charge of a task that might be related to money laundering. Through this, institutions may limit liability and eventually maximize their profit.