This final regulation sets forth the type of documentation required for an alien to establish the status of lawfully admitted for permanent residence for eligibility purposes under the Supplemental Security Income (SSI) program. The Immigration and Naturalization Service (INS), the Agency responsible for determining alien status and issuing documents certifying alien status in the U.S., changed its policy with regard to what constitutes definitive evidence of lawful permanent resident alien status. In this final SSI regulation, we are removing references to specific INS form numbers and substituting a general reference to an Alien Registration Receipt Card issued under current INS regulations. Thus, SSA's regulations will be broad enough not only to be consistent with the new INS policy, but also to accommodate future INS regulatory changes regarding acceptable documentary evidence of lawful permanent resident alien status. In the future, SSA will not have to revise its regulations to conform to changes in INS policy unless the form name changes. Historically, the form name has remained the same.