Advances in stem cell research provide great hope that these cells can be used to help tissue repair and avoid the need for complex surgery or organ transplantation. Despite extensive media coverage and enthusiasm for their therapeutic potential in patients, it may be years before such therapies reach their full potential. In this article, Dr Julie Crawford and Professor Marc Turner from the MRC Centre for Regenerative Medicine give a balanced view to help us decide whether stem cell therapy is ‘hype or reality’.