Manuela Simoni, MD, PhD, is Full Professor of Endocrinology, Department of Biomedical, Metabolic and Neural Sciences, University of Modena & Reggio Emilia, Italy. She is also Director of the Unit of Endocrinology, and Director of the Department of Medical Specialties of the of the Modena University Hospital, Italy. She was formerly University Professor of Endocrinology and Molecular Biology of Reproduction at the University of Münster, Germany. Dr. Simoni was Secretary of the European Society of Endocrinology and from 2010 to 2014 was a member of the Executive Council of the Italian Society of Andrology and Medical Sexology. She was Editor-in-Chief of the peer-reviewed journal ‘Andrology’ as well as Associate Editor of several renown journals in the field of reproductive endocrinology. She is the author of 332 papers in journals listed in Scopus, as well as more than 60 book chapters, and has an H-index of 67. Ilpo Tapani Huhtaniemi, MD, Dr. Med. Sci. (PhD), is Professor Emeritus of Reproductive Endocrinology, Institute of Reproductive and Developmental Biology, Department of Digestion, Metabolism and Reproduction, Imperial College London, London, UK. Prior to taking up this position in 2002, he served as Professor and Chairman of Physiology at the University of Turku, Finland for more than 15 years. Dr. Huhtaniemi has been the recipient of many awards and honors, including most recently the European Hormone Medal of the European Society of Endocrinology (2018). He was the Chief Editor of Molecular and Cellular Endocrinology 1999-2016 and is also past Editor of various other leading journals. He is a past president of the International Society of Andrology and past member of the Executive Council of the Europeans Society of Endocrinology (2011-15). He is the lead or co-author of approximately 750 peer-reviewed papers and >150 book chapters, and his H-indexes are 90 (Web of Science)/117 (Google Scholar). Daniele Santi, MD, PhD is Assistant Professor of Endocrinology at the Department of Biomedical, Metabolic and Neural Sciences, University of Modena & Reggio Emilia, Italy. He has published 135 manuscripts in peer-reviewed journals (ORCID: 0000-0001-6607-7105), with H-index of 30 (Scopus). In 2015, he obtained the ESE (European society of endocrinology) young investigator and the under-32 SIE (Italian society of endocrinology) awards. He is general secretary of and Italian society of medical andrology and sexual medicine (SIAMS) and member of the executive committees of SIE. He is associate editor a member of the peer-reviewed “Andrology”, “Frontiers in Endocrinology” and “Reproductive Medicine” journals. Moreover, he is the andrology section Editor for the new peer-reviewed journal “Reproductive, Female and Child Health”. He was editorial assistant of the peer-reviewed “Andrology” journal from 2018 to 2020. Channa Jayasena, MD, PhD is Reader and Consultant in Reproductive Endocrinology at Imperial College, St. Mary's and Hammersmith Hospitals, London, UK. He is also Head of Andrology, North-West London Pathology Services. Dr. Jayasena qualified in medicine at Cambridge University, after which he undertook specialist training in Diabetes & Endocrinology in London, and performed research at Imperial College as a Wellcome Trust Clinical Research Training Fellows and subsequently NIHR Clinical Lecturer. In 2018, Dr. Jayasena was awarded an NIHR Post-Doctoral Fellowship investigating the metabolic regulation of male infertility. Dr. Jayasena is also lead for the Society for Endocrinology (SfE) Specialist Endocrinology Network for Andrology. He also co-chaired the SfE UK Guidelines for management of hypogonadism.