The adult bone marrow contains mesenchymal stem cells. These cells show the capacity to undergo an extensive replication in vitro. In addition, mesenchymal stem cells have the potential to develop either in vitro or in vivo into mesenchymal tissues like bone and cartilage, which suggests these cells being an attractive source for tissue engineering approaches. Tissue engineering allows to isolate patient's own cells from tissue biopsies, to expand them, to combine them with carrier materials and growth factors, and to retransplant the constructs into the patient. Due to the prerequisite for tissue engineering to ensure a sufficient number of tissue-specific cells, much attention has been drawn to multipotential progenitor cells such as mesenchymal stem cells. In this article, important aspects of tissue engineering of bone and cartilage will be reviewed with emphasis on mesenchymal stem cells.