Much offshore financial activity by individual U.S. taxpayers is not illegal, but numerous schemes have been devised to hide the true ownership of funds held offshore and income moving between the U.S. and offshore jurisdictions. In recent years, there have been reports on several aspects of offshore financial activity and the tax compliance and tax admin. challenges such activity raises for the IRS. This report summarizes recent work describing individual offshore tax non-compliance, factors that enable offshore non-compliance, and the challenges that U.S. taxpayers' financial activity in offshore jurisdictions pose for the IRS.