In May 2008, the United States enacted the Consolidated Natural Resources Act (CNRA), amending the United States' Covenant with the Commonwealth of the Northern Mariana Islands (CNMI) to establish federal control of CNMI immigration in 2009, with several CNMI-specific provisions affecting foreign workers and investors during a transition. CNRA required this report on implementation of federal immigration law in the CNMI. The report describes the steps federal agencies have taken to: (1) secure the border in the CNMI; and (2) implement CNRA with regard to workers, visitors, and investors. The report reviewed federal laws, regulations, and agency documents; met with U.S. and CNMI officials; and observed federal operations in the CNMI.