Klaus Okkenhaug obtained his B.Sc. in Biochemistry from the University of Victoria, British Columbia, Canada, followed by a Ph.D. in Immunology from the University of Toronto, where he studied CD28 signalling in Rob Rottapel’s lab. In 1999, he moved to London, UK, where he joined Bart Vanhaesebroeck’s group at the Ludwig Institute for Cancer Research as a Postdoctoral Fellow, working on the role of the PI3K isoform p110δ in immune responses. Klaus joined the Laboratory of Lymphocyte Signalling and Development at the Babraham Institute as a Group Leader in 2003. His group investigates the role of cell signalling pathways in the immune system, with particular focus on the PI3K family of enzymes.