If you are going to be employed and do not already have a Social Security Number, you will need to apply for one through the Social Security Administration office located at the Federal Building at 3971 Research Park Drive, Ann Arbor, MI 48108. Find more information on the procedure at Getting A Social Security Number. You will need, among other documents listed, the U-M Social Security letter from the U-M International Center, which you received upon your arrival during J-1 Mandatory Check-In. If you lost this letter, contact the U-M International Center.