The IRS has launched a major offensive designed to uncover the existence of offshore bank accounts and other financial accounts. Federal regulations require taxpayers who have an interest in a foreign financial account to file what is known as a F-Bar Form (Report of Foreign Bank and Financial Account. The form number is TD F 90-22.1). In addition, such taxpayers are required to disclose an interest in foreign accounts on their tax returns. The IRS has begun to aggressively prosecute the failure to make complete disclosure of such accounts.