GAO discussed the continuing production of nuclear-powered attack submarines (SSN). GAO noted that: (1) there are less costly alternatives for maintaining the Navy's required SSN force structure; (2) the Navy could maintain low-rate production of the submarines or defer production until after year 2000; (3) the cost savings from deferring production would be offset by reconstitution costs for existing submarines; (4) the Navy based its approach on the perceived need to maintain a competitive industrial base for the submarines; (5) there is no consensus on the threat posed by Russian submarines because Russian operating capabilities, force readiness, and defense plans are uncertain; (6) although one shipbuilder's premise that consolidating shipbuilding at one shipyard would save money, there is insufficient time and information to validate its assumption; and (7) by consolidating shipbuilding operations, the Navy could order new ships as needed rather than providing sustained production.