Dennis J. Dietzen is the Megan K Dishop endowed Chair of Pathology and Laboratory Medicine at Phoenix Children’s Hospital. He was formerly a Professor of Pathology at Washington University in St. Louis and Director of Laboratory Services at St. Louis Children’s Hospital. He has been a member of ADLM/AACC and the Academy for nearly 30 years, serving as AACC President in 2018 and currently serves as Chair of the Policy and External Affairs Core Committee (PEACC). Dr. Dietzen’s research focus is mass spectrometry applications in pediatrics including rapid detection of drugs, metabolic disorders, liver failure, pre-eclampsia, and neonatal hypoglycemia. He has authored more than 100 peer-reviewed manuscripts, monographs, editorials, and book chapters.