Disclosed are methods for isolating endothelial progenitor cells (EPC). More particularly, the present invention discloses methods for isolating endothelial progenitor cells that exhibit self-renewal and differentiation capacity. The isolated cellular population of the present invention is useful in a wide range of clinical and research setting including inter alia, the in vitro or in vivo generation of endothelial cells and the therapeutic or prophylactic treatment of a range of conditions via the administration of these cells. Also facilitated is the isolation of endothelial progenitor cells for research purposes such as in vitro based screening systems for testing the therapeutic impact and/or toxicity of potential treatment or culture regimes to which these cells may be exposed to. The present invention also discloses methods for isolating mesenchymal stem cells, in particular mesenchymal stem cells of fetal and/or maternal origin. These cells are also useful in a range of in vitro and in vivo therapeutic, prophylactic and research applications.