The Defense Nuclear Facilities Safety Board is an independent Federal agency established by Congress in 1989. The Board is mandated to oversee the safety of the civilian nuclear weapons complex operated by the Department of Energy (DOE). The Board is viewed as an expert agency, capable of understanding the complexity of nuclear weapons facilities and operations. This annual report summarizes the Board’s activities during 2001 and includes all recommendations made by the Board the preceding year (2000). It presents an assessment of the improvements in safety of DOE defense nuclear facilities during 2001, the improvements in the safety of DOE defense nuclear facilities due to actions taken by the Board, and the outstanding safety problems of the DOE defense nuclear facilities. The report is divided into five sections. Section one, describes the goals and objectives of the Board's strategic plan. Sections two, three, and four describe the progress in the three major areas of the Board’s operations: safe management and stewardship of nuclear weapons, safe disposition of hazardous nuclear materials and facilities, and complex-wide safety issues. Section five addresses the Board’s interactions with the public. Appendices provide recommendations, technical reports issued in 2001, correspondence, administrative activities, and a list of abbreviations and acronyms.