Gene therapy has been successfully used in several areas of medicine as a technique to either alter defective genes or as method to enable delivery of therapeutic proteins. Despite advances in surgical and pharmaceutical interventions for diseases of bone regeneration and healing, results in certain patient groups remain sub-optimal. With this consideration, gene therapy is currently being investigated as a means of facilitating healing and improving outcomes. Two broad techniques which are currently utilised by research teams are discussed in this review; ex vivo and in vivo. The underlying principle is similar in each case; the use of gene therapy to alter target cells to deliver proteins which facilitate bone regeneration. However, whereas ex vivo techniques involve performing genetic manipulations outside the body and then introducing the altered cells to the desired site, in vivo techniques execute genetic manipulations inside the body by the introduction of vectors directly to the desired location. Results from small animal models for both techniques are promising, however, further research is required to demonstrate both safety and efficacy prior to any future clinical application.