Dr. Mario Marengo is a Medical Physicist and Radiation Protection Expert, former Director of the Medical Physics Department of the University Hospital of Bologna, S. Orsola–Malpighi. After his retirement in September 2018, he continues his professional activities as an Adjunct Professor for the University of Bologna and as a Technical Expert for the International Atomic Energy Agency. After he draduated in Physics and PhD in Medical Physics from the University of Bologna, he contributed to the design and construction of the PET Center of the S. Orsola Hospital, as well as of other PET and Nuclear Medicine Centers, both nationally and internationally. Dr. Marengo is an expert in quality systems in medicine and quality auditor. He is the author of on the Italian publication on— Physics in Nuclear Medicine — and has contributed to the IAEA publications on physics in nuclear medicine. He has co-authored over 90 original publications in peer reviewed scientific journals and numerous reports at national and international congresses.