Nikolaos G. Papaioannou comes from Trikala of Thessaly and completed the primary and secondary education in Athens. He studied at the Veterinary School of the Aristotle University of Thessaloniki, where he graduated with a degree of “very good 8.2”. Then he started the PhD thesis, which he supported in 1991 with an “excellent” degree. In 1995 he was elected lecturer at the laboratory of Pathological Anatomy of the Department of Veterinary Medicine. Since then, he has traversed all grades of the academic hierarchy and in 2012 he was elected professor of first grade. From 2013 to today he is the Director of the Laboratory of pathological anatomical, while from 2017 until 2019, chairman of the Department of Veterinary Medicine and deputy Dean of the School of Health Sciences of the Aristotle University of Thessaloniki. On June 11, 2019 he was elected Rector of the Aristotle University of Thessaloniki, taking on duties from September 1th of the same year. He has been a member of several committees of both the Department of Veterinary Medicine and the Aristotle University of Thessaloniki, as well as a member of the board of Directors of the Hellenic NARIC (2013-2017), President of the Board of Directors of the Hellenic Accreditation System (E. SY. D.), while from 2015 he is President of the Hellenic Veterinary Medical Society (HVMS). He has been trained in the laboratories of pathological anatomy of the veterinary schools of Zurich, Utrecht and Wisconsin of the United States of America while continuing the scientific-research activity with Colleagues of these laboratories. His educational work is related to the subject of pathological anatomical, while his scientific-research work focuses on histopathological and immunohistopathological study of disease lesions with emphasis on neuropathology, particularly dealing with the study of the pathogenicity of cognitive dysfunction. He is a member of Greek and international scientific societies: 1. Regular member of the Hellenic Veterinary Academy 2. Member of the Hellenic Veterinary Society. 3. Member of the Geotechnical chamber. 4. Member of the Panhellenic Veterinary Association. 5. Member of the Hellenic Society of Electron Microscopy. 6. Member of the Hellenic Society of Alzhaeimer. 7. Member of DEUTSCHEN VETERINÄRMEDIZINISCHEN GESELLSCHAFT 8. Member of the European Society of Veterinary Pathology (ESVP). 9. Member of Charles Lois Davis, D.V.M. Foundation (for the Advancement of Veterinary and Comparative Pathology) as well as reviewer of Greek and prestigious International scientific journals. He has supervised four (4) doctoral dissertations, in nine (9) he was a member of the three -member advisory committees and in twenty-five (25) member of the doctoral theses’ committees, resident and foreign. At post-doctoral level, he has collaborated and supervised foreign scientists who visited the laboratory of pathological anatomy in Thessaloniki, in matters of his expertise. He has participated/participates as a scientific coordinator or member of the research team in twenty-Siena (21) Competitive research national and European programs. He has participated as a speaker or guest speaker at eighty two (82) national and international conferences while he is chairman of the organizing committee of the 34th Conference of the European Society of Veterinarians in pathology (ESVP ), to be held in Athens in 2021. He has published alone or in collaboration with other researchers one hundred and ninety-six (196) scientific papers in prestigious journals of resident and abroad with a total influence ratio of 216, h-index 21 and i-10 index 43. His work so far has received 1995 petitions from other researchers. website: nikpap.webpages.auth.gr On 11 June 2019 he was elected Rector of the Aristotle University of Thessaloniki, taking on duties from 1 September of the same year.