Dr. Mathiesen is a globally recognized authority in the Arctic, focusing on reindeer husbandry, traditional knowledge, and Indigenous livelihoods. His academic journey began with a profound interest in the Arctic's complex biology and ecosystems. Svein Disch Mathiesen holds a PhD from the University of Tromsø (UiT), Department of Arctic Biology and Department of Medical Biology, Faculty of Medicine in 1999. He was employed as associate professor at UiT from 1989 to 2000 in physiology, focusing on reindeer nutrition and digestion. From 1997-2000 employed as a research fellow at the Norwegian Veterinary College. Between 2000 and 2014 was a Professor of zoo physiology at the Norwegian Veterinary College. From 2002 employed as researcher at the Nordic Sami Institute, (NSI) later - Sámi University College (SA).
Today, Dr Mathiesen is a permanent employee at the International Centre for Reindeer Husbandry (ICR) in Kautokeino, as head of the University of the Arctic EALÁT Institute, and also a tenure professor at Sámi University of Applied Sciences (Sámi Allaskuvla) in Kautokeino. Over the years, his work has bridged the gap between Indigenous reindeer herders, their knowledge of the Arctic, and academia, creating practical solutions to preserve biodiversity and cultural heritage. Svein D. Mathiesen leads groundbreaking research projects, mentors emerging scholars, and collaborates with international organizations to shape sustainable futures for the Arctic and beyond.
In 2023-2024, Svein D. Mathiesen co-edited and published two Reindeer Husbandry books - the result of many years of his efforts and dedication to elevating Indigenous knowledge, addressing climate change and enhancing resilience of reindeer herding peoples globally.

These books focus on climate change, Indigenous reindeer husbandry, and the underlying concept of connecting the traditional knowledge of Indigenous reindeer herders in the Arctic with the latest research findings of the world’s leading academics brought together by Dr Mathiesen.