Marlys H. Witte, MD, UA Professor of Surgery, Neurosurgery, and Pediatrics, Director of Student Research, University of Arizona College of Medicine, and Secretary-General of the 42-nation International Society of Lymphology. She is a world-recognized pioneer in clinical and basic lymphology – the study of lymphatics, lymph, lymphocytes, and lymph nodes in health and disease. She received her medical education at New York University School of Medicine, and post-graduate residency training at The University of North Carolina-North Carolina Memorial Hospital, New York University-Bellevue Medical Center, and Washington University in St. Louis/Barnes Hospital.  Her translational interests and contributions together with her late husband, Dr. Charles Witte, have ranged from blood/lymphatic vascular endothelial cell biology and pathobiology in vitro and in vivo, hepatosplanchnic lymphatic/microcirculatory physiology, small animal models, in vivo lymphatic imaging, thoracic duct lymph drainage, lymphogenous cancer spread, and genomics/proteomics of lymphedema-angiodysplasia syndromes in man, mice, and other animal models, including defects, deficiency, and overexpression of lymphangiogenesis genes VEGFR3 and FOXC2 (human) and Vegfc, Angiopoietin 2, and prox-1 (mouse) and their syndromic/phenotypic manifestations. Her collaborative research has touched upon HIV encephalopathy, blood-brain barrier, CNS fluid dynamics, and ocular development/ disorders. She continues to work with a variety of infectious diseases and immune disorders (e.g., AIDS, Kaposi sarcoma, tuberculosis, Whipple disease, inflammatory bowel disease, congenital/hereditary lymphatic system syndromes, opportunistic infections/neoplasms) and directs an internationally recognized Lymphedema-Angiodysplasia Clinic. Author of more than 400 peer-reviewed publications, recipient of numerous international honors and the UA College of Medicine's Gold-Headed Cane, Founders Day, and Virginia Furrow Education and Innovation Awards, she has received continuous funding from NIH (as well as other government, AMA, and non-profit agency grants) since she was a medical resident. She has served as Program Director of UA’s only NIH General Clinical Research Center (GCRC) and is a member of the UA Arizona Comprehensive Cancer Center, Sarver Heart Center, and Viper Institute and has mentored thousands of students in her career with a special interest in teaching "medical ignorance" – "what we know we don't know, don't know we don't know, and think we know but don't".