Covering nearly 4,000 miles of land and water from Washington to Maine, the U.S.-Canadian border is the longest undefended border in the world. The U.S. Customs and Border Protection, in collaboration with other fed., state, local, tribal, and Canadian entities have the primary responsibility for security. The Sec. of Homeland Security is required to submit a report to Congress that addresses the vulnerabilities along the northern border, and provides recommendations and required resources to address them. This report examined: (1) the extent to which the DHS report to Congress is responsive to the legislative requirements; and (2) actions that may be necessary to address northern border vulnerabilities in addition to the actions addressed in the report.