This document discusses extending a B1/B2 visitor visa while in the United States. It notes that visitors usually receive an I-94 status allowing 3-6 months stay, and to extend their stay beyond that period they must file Form I-539 to apply for an extension of stay before their I-94 expires. It recommends filing at least 60 days before expiration and provides examples of documents to include like bank statements, affidavits of support, and evidence of non-immigrant intent. It warns that if the extension is denied after the I-94 expires, unlawful presence could begin accruing and result in multi-year bans on reentry to the US or visa revocation.