One of the most important steps in the marriage green card process is for the couple to prove the relationship is legitimate and that they plan to build a future together. The U.S. government wants to know that they did not get married for the sole purpose of obtaining a green card. We’ve put together a detailed guide that explains the different types of documents an applicant can provide as proof, as well as which documents are considered stronger vs. weaker evidence. If the couple is currently living apart, there’s a section with alternative forms of proof they can provide.