The Bank Secrecy Act (BSA), enacted in 1970, requires financial institutions in the United States to assist government agencies in detecting and preventing money laundering and other financial crimes. It mandates that banks and other financial entities report certain transactions, maintain records, and implement anti-money laundering programs. Under the BSA, institutions must file reports for cash transactions exceeding $10,000 and suspicious activity that may indicate illegal activities. This law helps ensure that financial systems are not used for illicit purposes, promoting transparency and accountability within the banking sector.