Book excerpt: At the request of the Chief of Naval Operations, the National Research Council, under the auspices of the Naval Studies Board, established a committee to assess the Department of the Navy's current and future naval theater missile defense (TMD) capabilities. The Committee for Naval Forces' Capability for Theater Missile Defense first convened in April 2000 and met approximately 2 days a month for 8 months. This report is based on the information presented to the committee during that period and on the committee members' accumulated experience and expertise in military operations, systems, and technologies.