The basal layer of the human interfollicular epidermis is made up of a heterogeneous population of keratinocytes, giving rise to a self-renewing epidermis. Cell fate is dependent on the local environment, made up of both neighbouring epithelial cells, and adjacent dermal cells. This study examines the contribution of dermal cells to the regulation of epidermal homeostasis and regeneration. Using whole mount confocal microscopy with a range of markers we define the 3 dimensional position of different dermal populations with respect to the basal keratinocytes. These results identify specific populations in close proximity to the basement membrane, highlighting candidate keratinocyte regulators. One such population is the microvascular pericytes, previously shown by us to promote epidermal regeneration in vitro. Based on these observations, the functional ability of isolated pericytes and other dermal cells to promote long term keratinocyte self-renewal is being examined using an in vivo transplant model of human skin regeneration. These functional experiments are currently underway, and will be evaluated with respect to the extent and quality of skin regeneration obtained.