Unlike embryonic stem (ES) cells, adult somatic stem cell populations were originally thought to be committed to particular lineages. Recent work,however, suggests that they can be reprogrammed to form other lineages. This clearly has significant therapeutic implications — given the controversy surrounding use of human ES cells and the problems of bone marrow availability and extraction for transplantation — but whether such reprogramming reflects an innate property of these cells or is instead due to cell fusion or transformation events in culture is currently unclear. Colin Jahoda, Nick Hole and co-workers have examined the developmental potential of hair follicle cell populations (see p. 3967). They demonstrate that microdissected dermal papilla or dermal sheath (but not cells from the follicle epithelium) can generate erythroid and myeloid cells in vitro and yield multiple haematopoietic lineages for at least a year when cultured and transplanted into lethally irradiated mice. Since hair follicle cells are easy to isolate and display immune privilege, the finding that cells within this population are competent to produce a transplantable haematopoietic system has immense therapeutic potential.