The bid by the China National Offshore Oil Corporation (CNOOC) to acquire the U.S. energy company Unocal for $18.5 billion raised many issues with U.S. policymakers. This report provides an overview and analysis of the CNOOC bid, U.S. interests, implications for U.S. energy security, U.S. investment in the PRC’s (People’s Republic of China’s) oil industry, the process for reviewing the security and other implications of foreign investment in the United States, Congressional activity, and a listing of unresolved issues.