- Algebraic and geometric combinatorics, particularly the combinatorics of Coxeter groups and cluster algebras.
- Partially supported by NSF grant DMS-1101568.
- Triangle Lectures in Combinatorics, a twice-yearly research conference on combinatorics and related areas.
Partially supported by NSF grant DMS-1400355 and NSA grant H98230-14-1-0291.
- MA 724, Combinatorics II