x, 57 p. : ill. (mostly col.) / An extensive area west of the Three Sisters volcanoes of Oregon has been actively uplifting for over a decade. Examining the deformation is imperative to improve understanding of the potential hazards of Cascade volcanism and the emplacement of magma. I refine the timing of the onset of the deformation, resolve the change in uplift rates through time, and quantify the current deformation rate using Interferometric Synthetic Aperture Radar. The deformation is assessed in time and space using single interferogram InSAR, stacks of interferograms, and line-of-sight time series. I examine the shape of the deformation pattern and explore volcanic source parameters using a Mogi model and tension crack model with topographic corrections. By using the best fit model and combining all useable interferograms from different tracks, I create the first complete continuous inflation time series of the Three Sisters volcanic uplift from 1992 to 2010. / Committee in charge: Dr. David A. Schmidt, Chair; Dr. Katharine V. Cashman, Member; Dr. Joshua J. Roering, Member