Professor Caldararu's research is concentrated in Algebraic Geometry, with influences from String Theory and Homological Algebra. He is mostly interested in the study of derived categories, with applications in Algebraic Geometry. He has devoted most of his time to two special areas: twisted sheaves and their geometric applications (moduli problems, etc.), and Hochschild structures (homology, cohomology) of algebraic varieties and orbifolds. In the past few years he has also become interested in topics related to A-infinity algebras and their homology, and construction of categorical Gromov-Witten invariants.