Pursuant to a congressional request, GAO reviewed the Department of Energy's (DOE) fiscal year (FY) 2000 performance plan, which was submitted to Congress as required by the Government Performance and Results Act of 1993, focusing on the: (1) usefulness of the agency's plan for decisionmaking; and (2) degree of improvement the agency's FY 2000 performance plan represents over the FY 1999 plan. GAO noted that: (1) DOE's FY 2000 annual performance plan provides a limited picture of intended performance across the agency, a general discussion of strategies and resources the agency will use to achieve its goals, and limited confidence that agency performance information will be credible; (2) while the plan is clearly linked to the strategic plan, the strategic plan does not always provide quantitative goals and objectives that show what DOE plans to accomplish; (3) as a result, it is difficult for the user to determine whether the annual goals are reasonable and to measure how the Department's annual performance compares with the strategic plan's goals and objectives; (4) while the plan links annual performance to the program activities in the President's budget request, the plan would be more informative if it also presented all annual goals by the individual office; (5) although DOE recognizes the importance of validating and verifying performance measures and information systems required to assess its accomplishments, the annual plan does not translate that general recognition into specific plans for assessing and improving performance; (6) DOE's FY 2000 performance plan indicates moderate improvement in addressing the weaknesses GAO identified in its assessment of the FY 1999 performance plan; (7) in reviewing the FY 1999 plan, GAO observed that the performance plan did not: (a) provide an overall context for the measurement of performance addressed in the annual goals; (b) link all goals and measures to program activities in the budget request; (c) identify annual performance goals with crosscutting issues; (d) explain how strategies would contribute to achieving performance goals; and (e) provide details of the procedures to be used to verify and validate its performance; (8) among improvements in the FY 2000 plan are better linkage between annual performance and program activities in the budget request and strategies that are linked through strategic objectives to annual performance goals; (9) however, the annual performance plan could be improved by providing quantifiable strategic goals and objectives; and (10) these strategic goals and objectives would serve as a context for evaluating the Department's planned annual performance, identifying crosscutting issues with annual performance goals, and providing details showing how performance will be verified and validated.