Paul Fairchild speaks to Alexandra Hemsley, Assistant Commissioning Editor Paul Fairchild began his research career in Oxford, UK, where he studied for a doctorate within the Nuffield Department of Surgical Sciences, focusing on the immune response to organ allografts. After spending 5 years as a postdoctoral fellow investigating the etiology of autoimmune disease in the Department of Pathology, University of Cambridge, UK, he returned to Oxford, where he is currently a University Lecturer in Preclinical Medicine within the Sir William Dunn School of Pathology and a Fellow of Trinity College. In 2008, Fairchild founded the Oxford Stem Cell Institute (OSCI), for which he currently serves as Co-Director. As a highly interdisciplinary organization, the OSCI focuses on exploiting the properties of stem cells for the treatment of some of the most intractable chronic and degenerative diseases. It is within this context that he continues to apply his background in transplantation immunology, in order to investigate the nature of the immune response to tissues differentiated from pluripotent stem cells and to develop approaches to the induction and maintenance of immunological tolerance. In a recently published book, The Immunological Barriers to Regenerative Medicine, Fairchild explores the immunological challenges that face cell therapies and confronts some common misconceptions about the immunogenicity of pluripotent cells. Here, Fairchild speaks to Regenerative Medicine about why immunological issues cannot be ignored as stem cell science moves into the clinic.