In March 23-25, 2005, an international symposium on red alder was held at the University of Washington Center for Urban Horticulture in Seattle, WA. The symposium was entitled S2Red alder: A State of KnowledgeS3 and brought together regional experts to critically examine the economic, ecological and social values of red alder. The primary goal of the symposium was to discuss new advances in the understanding of red alder biology and silviculture, changing market and nonmarket values, and the current regulatory climate for management of alder. This proceedings includes 14 papers based on oral presentations given at the symposium. These papers highlight some of the key findings from the history, ecology, biology, silviculture and economics sessions presented at the red alder symposium.