MSCs were first identified by Friendenstein and colleagues as an adherent stromal cell population within the bone marrow with the ability to form clonogenic colonies in vitro.  In regards to the basic biology associated with MSCs, there has been tremendous progress towards understanding this cell population's phenotype and function from a range of tissue sources.  Despite enormous progress and an overall increased understanding of MSCs at the molecular and cellular level, several critical questions remain to be answered in regards to the use of these cells in therapeutic applications.  Clinically, both autologous and allogenic approaches for the transplantation of MSCs are being explored.  Several of the processing steps needed for the clinical application of MSCs, including isolation from various tissues, scalable in vitro expansion, cell banking, dose preparation, quality control parameters, delivery methods and numerous others are being extensively studied.   Despite a significant number of ongoing clinical trials, none of the current therapeutic approaches have, at this point, become a standard of care treatment.  Although exceptionally promising, the clinical translation of MSC-based therapies is still a work in progress.