So you're not a permanent permanent resident? Apparently not. The Permanent Resident Card, the "green card," is not merely an identification document allowing you to live and work in the US, it is also proof of your status. And, like everything of this world, your green card is not going to last forever. Green cards expire. They get old. And like a lot of things, when they get old, they don't work anymore. Most green cards are good for ten years. Green cards issued many, many years ago are so old that they don't even have an expiration date, but they should be replaced anyway. Some green cards are good for two years. These two types of cards, the ten year cards and the two year cards are different and cannot be renewed the same way. Cards which have a ten year expiration date are replaced by filing form I-90 at where ever the appropriate processing center of the moment is currently located. (This shuffle of appropriate processing centers happened with alarming regularity under the last Republican administration). For the moment all paper I-90s are filed in Phoenix, Arizona. Cards that have a two year expiration date require the filing of form I-751 with either the California or the Vermont Service Center. These darn locations seem to change often, so check the right address at www.uscis.gov, clicking on the word "forms" "FORMS," and scrolling down. (I should note that this article is not discussing temporary investor/entrepreneur green cards. These special green cards have their own rules.) Allowing either type of green card, the two year or the ten year, to expire results in different consequences. For the ten year card, technically, allowing the green card to expire simply results in losing one's proof of Lawful Permanent Residence. You might get stuck outside the US if you travel abroad, with no effective proof of your Lawful Permanent Residence to get you back in the US. Or you might simply find it difficult to obtain employment. However, allowing the two year green card to expire results in one becoming deportable. Allowing either card to expire would be regrettable, but allowing the two year card to expire would be more than regrettable, it would result in becoming removable. Lawful Permanent Residents ("LPRs") who became LPRs before they turned 14 years old are required to replace their green card when they turn 14. Where can you get the instructions for filing and the forms themselves? The forms are available at www.uscis.gov. Go to the website and click on the word "forms" or "FORMS." On the next screen scroll down to whatever form you need. Form I-751 is for an expiring two year green card. Form I-90 is for an expiring ten year green card. When do you file form I-90? Well, unless you need to replace the green card because of a name change, or because it got lost or stolen, you would file the I-90 no more than six months before the ten year green card expires. When do you file form I-751? Before your green card expires, but not earlier than 90 days before the two year green card expires. Disclaimer: This comes as general information, and is not intended for specific applications. I suggest discussing your personal details with an experienced immigration attorney.