In recent decades, managing the nation's public and private forests and rangelands has become increasingly complex, requiring a sound understanding of science and science-based tools to address these complexities. The Department of Agriculture's Forest Service maintains a research and development program (FS R&D) to help provide scientific information and tools. This book examines the scope of research and development carried out by FS R&D and some of its resulting accomplishments; trends in resources used in performing FS R&D work and the effects of those trends on its research efforts and priorities and recent steps FS R&D has taken to improve its ability to fulfil its mission and the challenges it faces in doing so.