Summary: The Strategic Defense Initiative Organization (SDIO) cannot estimate total cost and personnel requirements for the planned theater missile defense system because it has not fully defined the design and performance requirements for the overall capability. For the functional element upon which it has concentrated--active defense--SDIO has not yet developed an overall program plan that defines how theater missile defense will interact within its own elements, with existing air defense capabilities, or with other components of the Global Protection Against Limited Strikes system. Further, SDIO has not yet developed an overall program plan and acquisition strategy for acquiring and deploying the systems and has not fully defined certain performance requirements. SDIO projected that it would need about $2.4 billion more funding during fiscal years 1992 through 1997 than had been approved for the theater missile defense program in the Department of Defense's fiscal year 1993 plan. SDIO officials said that the fiscal year 1994 plan would include enough funding to implement the currently planned program. Although the Army does not know its total theater missile defense force requirements, it has estimated that it will need about 1,300 people for the Theater High Altitude Area Defense system and has stated that no new personnel would be required if the upgraded Patriot system is selected for lower tier defense. The Pentagon is required to provide Congress with a master plan covering the theater missile defense program when the President submits his 1994 fiscal year budget.