Jon Aster obtained his MD/PhD in 1987 from the University of Michigan, and then did clinical training in Anatomic Pathology and hematopathology at Brigham and Women’s Hospital. During his postdoctoral work in the Division of Molecular Oncology with Dr. Jeffrey Sklar, he developed an interest in the role of Notch signaling in cancer and hematopoiesis, areas of research that he has continued to pursue to the present. Over the years his lab has led or collaborated on work that has produced a number of firsts in the field, including: i) production of the first mouse model of Notch leukemia; ii) demonstrating that Notch signals can induce T cell development from bone marrow progenitors; iii) demonstrating that T-ALL cells depend on continuing Notch signaling for growth; iv) detecting and characterizing frequent Notch1 mutations in human and murine T-ALL; v) solving key Notch structures at high resolution, including the structures of Notch transcription complexes on DNA; vi) identification of Myc and mTOR as important downstream targets of leukemogenic Notch signaling; vii) development of the first selective Notch receptor inhibitors, antibodies directed against the negative regulatory domain; viii) report of genome-wide Notch1 binding patterns in cancer cell genomes; and viii) description of Notch1 loss-of-function mutations in human squamous cell carcinomas. His work describing Notch1 mutations in T-cell acute lymphoblastic leukemia is one of the most highly cited in the field (2265 citations). He has led multi-investigator multi-institution NIH funded Program Project Grants and Leukemia and Lymphoma Society sponsored Specialized Center of Research Grants. Since 2007, Aster is full Professor of Pathology at Brigham and Women’s Hospital and Harvard Medical School and as of 2017 is the first incumbent Michael A. Gimbrone Chair in Pathology. Aster has published more than 190 manuscripts in peer-reviewed journals that have been cited more than 55,000 times and an h-factor of 104. He holds 3 patents. He has been an invited speaker at all major international meetings focused on Notch signaling in cancer to date (the Notch Gordon conference, the International Notch Meeting), and has organized several of these meetings. He leads the division of Hematopathology at Brigham and Women’s Hospital, serves as the co-leader of the Lymphoma and Leukemia Program of the Dana Farber/Harvard Cancer Center, and is on the Executive Committee of the Cancer Center. He is a past member of the NIH Cancer and Molecular Pathology study section, and continues to serve as an ad hoc reviewer for the NIH. In 2017, Aster was elected to the Association of American Physicians. He also is the co-editor of the Pathologic Basis of Disease, the most widely used pathology text in the world.