U.N. inspections of Iraq's weapons of mass destruction (WMD) programs resumed in November 2002 after a 4-year hiatus. U.N. Security Council Resolution 1441 granted Iraq a final chance to disarm. Given Iraq's history of thwarting WMD inspections, many have low expectations for the success of inspections. This report, which will be updated, analyzes the challenges and opportunities of inspections in light of new U.N. Security Council authorities and Congress's authorization to use U.S. force against Iraq (P.L. 107-243). The success of these inspections will have a direct impact on whether U.S. military force is used to eliminate the threat of weapons of mass destruction in Iraq. On the plus side, new inspections have strengthened authorities under the new U.N. resolution, including unimpeded access to all sites and interviewing Iraqi officials privately, and they utilize new technologies. There is also a better relationship between U.N. Monitoring, Verification, and Inspection Commission (UNMOVIC) and the International Atomic Energy Agency (IAEA) than there was between its predecessor and the IAEA. Inspections, rather than military strikes, could encourage defectors to provide critical information and might facilitate uncovering links between WMD and terrorism. Inspections conducted under the threat of military strikes have likely increased the pressure on Iraq to comply. On the negative side, inspectors face new practical, technical, and political challenges. New regulations for sharing intelligence and inspector recruitment may hinder inspections and Iraq has had four years to potentially hide weapons activities in dual-use facilities. The threat of war could increase pressure on inspectors to produce some definitive knowledge and could potentially politicize their investigations.