The Plate Boundary Observatory (PBO), which is part of the larger NSF-funded EarthScope project, is nearing the end of year 3 of the installation phase of 852 continuously operating GPS stations in the Western United States. The Pacific Northwest (PNW) region will install 134 continuous GPS stations by the end of September 2008. The sites are distributed along the fore and back-arc of the Cascadia Subduction Zone and at Mt. St. Helens. At the end of September 2007, the PNW region will be several stations short of its installation goal of 110 GPS stations, mostly due to an unusually early and high danger wildfire season. The scientific priority during this past year was to concentrate installations in the Oregon back arc region, the Southwest Oregon fore arc region and the Idaho panhandle. In the last year UNAVCO has added 10 stations to the Pacific Northwest region, raising the number of stations from 124 to 134. The majority of these stations are located within the fore and back arc regions of Southern Oregon. In addition the UNAVCO installed its first building mounted site within a difficult area along the Southwest Oregon coast. UNAVCO will install its remaining 24 new continuous GPS stations in the Pacific Northwest in year 5. The remaining stations are distributed throughout the region, and comprise a mix of standard monuments, and strainmeter collocations. Our goal is to have all stations installed by August 31 2008. Reconnaissance work for all of the GPS sites have been completed, and have had permits submitted.