Contrary to popular myth, immigrants who marry U.S. citizens do not become green card holders right away, or automatically. In fact, the first green card that they receive is, in some cases, not the same as other green cards. It has a two-year expiration date. This is the case for immigrants whose marriages to the U.S. citizen had not yet reached their second anniversary at the time they were approved for U.S. residence or entered the U.S. on an immigrant visa. It is very important for conditional residents to understand that if they don't take action before the two-year expiration date of their green card, and apply to have the "conditions" removed and become permanent residents, they will lose their rights to a green card or to remain in the United States.