When a U.S. citizen, residing in the United States, marries an alien, the alien is eligible to receive a “green card” based on that marriage. If you are a U.S. citizen, your spouse is considered an "immediate relative" and he or she may apply for permanent residency. In order to be granted permanent residency, your spouse's relationship with you must be established and your spouse must be admissible to the United States under the immigration law. Also, the marriage must be bona fide, not merely a sham to get the alien a green card. The INS takes fraudulent marriage seriously and you will be asked to provide supporting documents to show that the marriage is valid.