Cellular therapy involves the isolation, expansion, and transplantation of human cells for the replacement or regeneration of injured tissues. It is one of the most significant tissue repair strategies in the emerging discipline of regenerative medicine. Cellular strategies have been applied in joint repair for the treatment of acute cartilage injury, meniscal repair, and osteoarthritis (OA). Many of these efforts have been motivated by the apparent incapacity of cartilage to repair itself and the observation that initial trauma is likely to lead to sustained joint degeneration. A particularly important question that arises about cellular therapy in OA relates to the long-term outcome of these procedures. In addition, questions remain about the most suitable cell source, the advantages of allogeneic over autologous therapy, their potential uses in late stage OA, and, not least, the logistics of manufacturing and supply. These topics are discussed in this review, as well as an evaluation of knowledge gaps and technical obstacles that remain to be addressed.