Following his graduate work, Dr. O'Donnell moved to Washington University in St. Louis, MO as a postdoctoral fellow in the Physics Department working on applications of ultrasonics to medicine and non-destructive testing. He subsequently held a joint appointment as a Senior Research Associate in the Physics Department and a Research Instructor of Medicine in the Department of Medicine at Washington University. In 1980 he moved to General Electric Corporate Research and Development Center in Schenectady, NY, where he continued to work on medical electronics, including MRI and ultrasound imaging systems. During the 1984-1985 academic year, he was a visiting fellow in the Department of Electrical Engineering at Yale University in New Haven, CT investigating automated image analysis systems. In 1990, Dr. O'Donnell became a Professor of Electrical Engineering & Computer Science at the University of Michigan in Ann Arbor, MI. Starting in 1997, he held a joint appointment as Professor of Biomedical Engineering. In 1998, he was named the Jerry W. and Carol L. Levin Professor of Engineering. From 1999-2006, he also served as Chair of the Biomedical Engineering Department. During 2006, he moved to the University of Washington in Seattle, WA where he was the Frank and Julie Jungers Dean of Engineering until the end of 2012. He is now a Professor of Bioengineering and Frank and Julie Jungers Dean Emeritus. His most recent research has explored new imaging modalities in biomedicine, including elasticity imaging, in vivo microscopy, optoacoustic arrays, photoacoustic contrast agents for molecular imaging and therapy, thermal strain imaging, and catheter-based devices.