Cell Science at a Glance 1179 interactions during development and in postnatal life (Blanpain and Fuchs, 2009; Müller-Röver et al., 2001; Schmidt-Ullrich and Paus, 2005; Watt and Jensen, 2009). One population of mesenchymal cells in the skin, known as dermal papilla (DP) cells, is the focus of intense interest because the DP not only regulates hair follicle development and growth, but is also thought to be a reservoir of multipotent stem cells. In this article and the accompanying poster we review the origins of the DP during skin development, and discuss DP heterogeneity and the changes in the DP that occur during the hair growth cycle. We also consider the different cell lineages along which DP cells can differentiate as well as potential clinical applications of DP cells.