August 1978 – August 1982, Graduate Research Assistant and Principal Teaching Assistant, Department of Mechanical Engineering, Clemson University, Clemson, S.C.
August 1982 – August 1983, Visiting Assistant Professor, Department of Mechanical Engineering, Clemson University, Clemson, S.C.
September 1983 – June 1986, Assistant Professor, Department of Engineering Science and Mechanics, University of Tennessee, Knoxville, Tenn.
August 1986 – June 1988, Associate Professor, Department of Aerospace Engineering, Mechanics, and Engineering Science, University of Florida, Gainesville, Fla.
June 1998 – July 1991, Development Staff Member and Program Manager, Composite and Space Structures Technology Group, Oak Ridge National Laboratory, Oak Ridge, Tenn.
July 1991 – October 1995, Program Manager, Air Force Office of Scientific Research, Washington, D.C.
October 1995 – August 1998, Deputy for Research Sciences, Office of the Assistant Secretary of the Air Force (Acquisition), Science, Technology and Engineering, Washington, D.C.
August 1998 - June 1999, Student, Industrial College of the Armed Forces, Washington, D.C.
June 1999 – June 2001, Chief Technologist, National Security Space Architect, Fairfax, Va.
June 2001 - January 2002, Senior Program Analyst, Office of the Deputy Director of Central Intelligence for Community Management, George Bush Center for Intelligence, Washington, D.C.
January 2002 – August 2005, Director, Aerospace and Materials Sciences, Air Force Office of Scientific Research, Arlington, Va.
August 2005 – September 2007, Director, Plans and Programs, Air Force Research Laboratory, Wright-Patterson AFB, Ohio
September 2007 – July 2018, Executive Director, Office of Naval Research (ONR), Department of the Navy, Arlington, Va.
July 2018 – August 2019, Executive Director, Navy International Programs Office, Department of the Navy, Washington, D.C.
August 2019 – June 2020, Professor of the Practice, J. Mike Walker ’66 Department of Mechanical Engineering, Texas A&M University, College Station, Texas
June 2020 – June 2021, Executive Director, Rice University National Security Research Accelerator, Professor in the Practice, Department of Mechanical Engineering, Rice University, Houston, Texas
June 2021 – present, Director and Chancellor, Air Force Institute of Technology, Wright-Patterson AFB, Ohio