Selective Service - Check Yes. and go to www.sss.gov and register. If you do that you will be fine. If your friend checked no, but he still registered then he will also be fine, they will just change his answer at the interview. If your friend was not a green card holder before turing 26, but instead was in some other status, like F1 student, then he was not required to register. If you don't know if your registered (you may have done so in High School or college) then go the www.sss.gov and register. Time to Apply - If you apply any earlier than 4 years and 9 months after becoming a permanent resident, then your application will be rejected, no exceptions, and you will loose your $400. (unless you are married to a US citizen. In that case it is 2 yrs 9 months IF you have been married for a full 3 yrs and your spouse has been a citizen for a full 3 yrs) Please get these things straight, and don't trust just anyone that thinks they can answer on Sajha. (Except me, I happen to know what I am talking about)