- ILAS Speaker, SIAM Conference on Applied Linear Algebra, 2021
- Plenary Speaker, Southeastern Combinatorics Conference, 2021
- ELA Lecture, SIAM Linear Algebra Conference, 2020
- Lifetime Ellbogen Award, University of Wyoming, 2019
- A&S Top 10 Prof, 2004, 2006, 2009
- A &S Exemplary Faculty Award, 2009
- Plenary Lecturer, IMA PI Summer Program on Linear Algebra & Applications, 2008
- ILAS-SIAM Lecturer, 2008
- Olga Taussky-John Todd Lecturer, International Linear Algebra Society, 2007
- George Duke Humphrey Award, the highest honor for faculty at the U. Wyoming,
- 2006
- Outstanding Graduate Mentor, 2006
- Rocky Mountain Section MAA, Burton Jones Teaching Award, 2005
- ILAS-SIAM Lecturer, 2003
- Ellbogen Outstanding Teacher; the highest recognition for teaching at U. Wyoming, 1997 Warming up the Chill Award, Ellbogen Center for Teaching Excellence 1997
- A &S Extraordinary Merit in Research, 1991, 1996
- Young Scholar Award at Int’l Graph Theory Conference in Kalamazoo, Michigan, 1992
- Outstanding Teaching Assistant Award, University of Wisconsin-Madison, 1989