Bergström received his PhD 1981 from the Royal Institute of Technology, with a thesis by the title of ``Aspects of bound states in hadron physics". After a postdoctoral fellowship at CERN, he was nominated docent in theoretical physics at the Royal Institute of Technology. Afterwards, he was appointed professor of theoretical physics at Uppsala University, before becoming associate professor at Stockholm University in 1995. From 2008 to 2014 he has served as director of the Oskar Klein Centre for Cosmoparticle Physics.