The term "Adjustment of Status" refers to the many-months long process that some intending immigrants living in the United States use to apply for permanent resident status (a green card). After filing an Adjustment of Status application, the intending immigrant is allowed to live legally in the United States and apply for a work permit while awaiting an interview at an office of U.S. Citizenship and Immigration Services (USCIS). At that interview, or soon after, the application for permanent residence will normally be either approved or denied.
However, the wait for an interview is often many months long, and numerous immigrants wish to travel outside the United States during that time. Perhaps they'd like to visit their home country or simply take a vacation. But without advance planning, such travel can destroy one's immigration case. For starters, if the immigrant doesn't apply for an receive what's called "Advance Parole" before leaving, USCIS will assume the immigrant is no longer interested in the green card and is "abandoning" the application. USCIS will then cancel the case and you'd have to start over.
By applying for Advance Parole, you can get a travel document that gives you permission to return to the United States in order to resume your Adjustment of Status application when your travel is completed. Fortunately, it's easy to apply for, using a form that you'll submit at the same time as your Adjustment of Status application.
You can apply for Advance Parole using USCIS Form I-131, available on the USCIS website. You won't even have to pay the fee that other people do. It's included in your Adjustment of Status application fee.
Here are a few crucial things to know about Advance Parole.
There are exceptions to the Advance Parole requirement.
If you hold a valid H-1, H-4, K-3, K-4, L-1, L-2, V-2, or V-3 visa or status then you may travel without Advance Parole approval. For example, if you are traveling for the same employer that your H or L visa was issued for then you don't need Advance Parole. The H or L status must be valid and you must have evidence that you filed an Adjustment of Status application.