• 2008-present, Professor of Mathematics, Middlebury College. Department Chair from 2018—2022.
• 2022—2023, Visiting Fellow, University of Otago, Dunedin, New Zealand.
• Fall 2016, Visiting Research Fellow, Harry Ransom Research Center, University of Texas at Austin
• 2008-2013, co-Editor of Math Horizons, quarterly journal published by the MAA
• 2010-2011, Visiting Fellow, Clare Hall College and CRASSH (Center for Research in the Arts, Social Sciences and Humanities), Cambridge University
• 2002-2008, co-Head of Ross Commons, Middlebury College
• Spring 1999, Visiting Assistant Professor, University of Virginia
• 1992-1993 and 1995-1996, Visiting Assistant Professor, Saint Olaf College
