Barbara Cannon, Professor Emeritus in the Department of Molecular Biosciences at Stockholm University, died on January 5th, 2026, in her 79th year. She is survived by her husband of forty-seven years, Jan Nedergaard, two sons and their families. Barbara grew up in north-west England, obtained a BSc in Biochemistry from London University and a PhD in Physiology from Stockholm University. She joined the faculty of Stockholm University in the 1970’s and rapidly rose through the ranks to Professor in 1983. Barbara and Jan had a joint interest in the control of thermogenesis, with an emphasis on development and metabolism of brown adipose tissue and the impact of environment on thermoregulation in small mammals. Many of their publications are fundamental to the field and provide a new, carefully established perspective on adaptive thermogenesis in both rodent models and humans. Barbara received many awards in recognition of her research, including Honorary Doctorates from three universities. In 2016, the Emperor of Japan awarded her the Order of the Rising Sun, Gold and Silver Star for distinguished achievements in the field. Barbara also contributed to the advancement of science through service at the local, national and international level. She was inducted into the Royal Swedish Academy of Sciences in 1989 and subsequently served as vice-President and President. Barbara also played an important role as a Trustee in the Nobel Foundation, serving as Chairman from 2008 – 2011, receiving the King’s Medal, the ribbon of the Order of the Seraphim, for exceptional service to the Swedish scientific community. Barbara was a long-time supporter of SSIB and a Keynote speaker at several annual meetings. Despite her distinguished and demanding career, Barbara always had time to mentor and encourage both established and young scientists and will be remembered around the world for her generosity of spirit, time and expertise. Her friendship and support will be missed by many.