Most surgical heart valves currently implanted are bioprosthetic tissue valves. Such valves deteriorate with time, eventually presenting with either stenosis or regurgitation. Reoperation, the current standard of care for failed valves, carries significant risk in terms of both morbidity and mortality. Implantation of a transcatheter valve inside a failed surgical valve (valve-in-valve procedure) has recently emerged as an alternative, less-invasive option. Although the procedure is similar in some aspects to transcatheter aortic valve implantation in the setting of native aortic valve stenosis, there are many differences that deserve special consideration. We review the potential and challenges of valve-in-valve implantation in patients with failing surgical aortic bioprostheses.