The Puget Sound River History Project studies the historical landscape of Puget Sound's lowland rivers and estuaries as a dynamically linked geophysical, ecological, and human system. The historical emphasis is on conditions at the time of earliest Euro-American settlement in the mid-19th century, but also includes the landscape's post-glacial, Holocene (10,000 yrs BP) evolution and the last century and a half of change. We undertake interdisciplinary research that integrates archival investigations, field studies, and the tools of geographic information systems and remote sensing. We also apply the results to, and make data available for, regional problems of resource management, restoration and planning.