The information provided in this report documents that the National Science Foundation (NSF) is a well-managed and effective organization with an outstanding staff dedicated to ensuring that America's future is secure and prosperous. Despite its small size, NSF is widely recognized as the catalyst for the advancement of basic research in America. NSF funds research that opens new frontiers of scientific inquiry and contributes to developing a competitive workforce in science and engineering. Advances in science and engineering such as development of the next generation of medical devices that incorporate nanoscale engineering and technology; the development of new sensors and filters that will protect buildings against chemical attack; supercomputing systems with the capability to process ten trillion calculations per second, are critical for securing the homeland, sustaining economic prosperity and advancing the quality of life for society as a whole. The agency successfully achieved 27 of 30 performance goals, again exceeding its principal customer service goal of informing at least 70 percent of applicants about funding decisions within six months. During FY 2004, a record 43,817 proposals were received, and nearly 10,400 awards were made. For the seventh consecutive year, NSF has received an unqualified opinion on its financial statements. As required by section 1116(e) of title 31 of the United States Code, the agency reports that the financial and performance information contained in this report is complete and reliable. NSF also reports that it is in substantial compliance with the requirements of the Federal Managers' Financial Integrity Act of 1982 (FMFIA) and the Federal Financial Management Improvement Act of 1996 (FFMIA), and that there are no material weaknesses in the agency's management controls. This assessment is based on an independent external consulting firm's recent verification and validation review of the agency's Government Performance results; NSF Management Controls Committee's organizational review conducted in late summer; and the Independent Auditor's Report received on November 5, 2004. The Foundation continually strives to do more with less and work smarter by instituting more efficient and cost-effective business processes. The following are appended: (1) Description of NSF Directorates and Management Offices; (2) NSF Executive Staff; (3) National Science Board Members During FY 2004; (4) Improper Payments Information Act: Reporting Details; (5) Schedule of Program Evaluations; (6) Table of External Evaluations; and (7) List of Acronyms.