The U.S. visa (stamp or sticker in your passport) is a travel document which allows entry to the United States with a valid DS-2019. You only need to have a valid J visa when you are re-entering the U.S.; you may remain in the U.S. with your valid DS-2019. If you plan to travel and re-enter the U.S. from abroad after your visa has expired, you need to apply for a new visa before you re-enter. You can only apply for the visa outside the country at a U.S. Consulate. Please read the detailed information on our website about travel and visa application for further details.