The Financial Crimes Enforcement Network (FinCEN) is a bureau of the U.S. Department of the Treasury. It was established to combat money laundering and other financial crimes. FinCEN collects and analyzes financial transaction data to identify and prevent illicit activities, such as terrorism financing and drug trafficking. FinCEN works closely with law enforcement agencies, financial institutions, and international partners to enhance the security of the financial system. It issues regulations and guidelines to help institutions report suspicious activities, ensuring compliance with the Bank Secrecy Act and other relevant laws.