How do the heterogenous epithelial, endothelial, neural, myeloid and other cells that make up the thymic stromal cell population direct the homing, migration, differentiation, and selection of multi-potent hematopoietic progenitor cells to generate a diverse and self-tolerant population of T cells? We investigate the mechanisms regulating T cell development and tolerance and how these processes change during aging, with the ultimate goal of improving T cell immunity and tolerance in the aging population. As a lab, we also aim to create an encouraging and rigorous environment to train a diverse new generation of excellent biomedical scientists.