The ability of stem cells to participate in brain repair has been increasingly demonstrated in recent studies. Most investigations have aimed to replace damaged neurons and glia by direct transplantation or recruitment of newly generated cells in the adult. However, functional improvements were often a result of stem cell-induced self-repair and neuroprotection, rather than cell replacement. Thus, a far more pragmatic approach in the short term might be to use stem cells as chaperones for degenerating nervous tissues. Additionally, targeted delivery of therapeutic agents could be achieved by modifying stem cells to release specific drugs at the site of transplantation. Elucidation and exploitation of this new ‘stem cell pharmacology’ has the potential to revolutionise treatment of neurological diseases.