The recent listing of Pacific salmon under the Endangered Species Act has led to substantial interest in the scientific basis for river restoration in the Pacific Northwest. Millions of dollars in state and federal funding have been programmed for habitat restoration efforts to stem the decline of salmon populations in the region. This volume addresses the need for a solid understanding of fluvial processes and aquatic ecology in order to predict both river and salmonid response to restoration projects. In the Pacific Northwest, as in most regions of the United States, we are still learning about the processes that create habitat and river structure, how those processes influence aquatic ecosystems, and how to gauge the response of river systems to both land-use changes and restoration efforts. River systems are still responding to historic changes, and degraded habitat may not be restored successfully if natural conditions are not well understood, particularly if massive changes in watershed hydrology or other processes are the root cause. These issues faced in the development of regional river restoration programs are by no means unique to the Northwest, and so the initiation of a regional program of river restoration provides an opportunity to evaluate the state of river restoration in general. The eighteen chapters of Restoration of Puget Sound Rivers--presented by the region's experts at a symposium of the Society for Ecological Restoration--examine geological and geomorphological controls on river and stream characteristics and dynamics, biological aspects of river systems in the region, and the application of fluvial geomorphology, civil engineering, riparian ecology, and aquatic ecology in efforts to restore Puget Sound Rivers. This volume will be of interest to geomorphologists, aquatic biologists, civil engineers, planners, and all those interested in the interface of science and policy in addressing one of the fundamental environmental challenges of the twenty-first century.