U.S. citizens and Legal Permanent Resident Aliens are responsible for filing U.S. federal income tax returns while living overseas.  The Internal Revenue Service has comprehensive information on how to file from abroad, the regulations and procedures you must follow, and a wide variety of forms and publications to guide you through each step of the process.  Answers to many frequently asked questions for those living abroad regarding taxes are available on-line along with the application for Individual Taxpayer Identification Number.  If you are transporting currency or monetary instruments abroad, or back to the United States, you will need to file the appropriate report.