Dr. Mark M. Davis is the Burt and Marion Avery Family Professor of Immunology at Stanford University. Dr. Davis has been an investigator at the Howard Hughes Medical Institute since 1987. He is also a member of National Academy of Sciences, American Academy of Arts and Sciences, and National Academy of Medicine. Since his ground-breaking cloning of T cell antigen receptor genes (TCR) in 1984, Dr. Davis has been a pioneer and leader the field of molecular immunology. Specifically, by pushing the boundaries of knowledge in multiple areas, such as antigen receptor recognition, thymic selection, and B cell terminal differentiation, his discoveries shaped our understanding of self versus nonself discrimination, the most fundamental question in adaptive immunity. In addition, the Davis lab is the acclaimed source of technology integration and innovation. The application of protein chemistry, biophysics, and live cell imaging in the Davis lab have made the study of T cell recognition the most advanced and quantitative of any system of cell-cell recognition in biology. Technologies developed in the Davis lab, such as peptide-MHC tetramers, have become standard tools in basic and clinical immunology studies. In 2004, Dr. Davis became the founding director of Stanford Institute for Immunity, Transplantation and Infection and an advocate of human immunology. He then changed his lab’s focus away from basic immunology to studies of the human immune system. Here, he has also had a tremendous impact, developing more advanced ways to monitor immunity and responses clinically, and integrating repertoire sequencing, single cell genomics and proteomics technologies to challenge immunological dogma and the power of human work to contribute to basic immunological principals. His innovations and dedication have opened a new chapter in human immunology and translational medicine.