The unmet need for therapies capable of repairing the central nervous system (CNS) damage occurring in many diseases including multiple sclerosis (MS) has sparked the interest of the neurological community for stem cell-based therapies. An exhaustive amount of preclinical data has shown that the intravenous administration of mesenchymal stem cells (MSC), a subset of progenitor cells isolated from many mesodermal tissues, effectively ameliorates experimental autoimmune encephalomyelitis (EAE), a model of MS, through the release of anti-inflammatory and neuroprotective molecules. Based on these results, several small pilot clinical trials in subjects with advanced MS have demonstrated that MSC administration is safe and provided an early signal of clinical effectiveness. The current aim of clinicians and scientists interested in the development of MSC-based strategies for the treatment of MS is to have the ultimate demonstration in large clinical trials that MSC can inhibit CNS inflammation and foster tissue repair as realized clinically, with functional recovery, or visualized by magnetic resonance imaging (MRI).