Culture of adipose tissue precursor cells allows gaining insight into the sequential processes involved in adipocyte development. Furthermore, the secretory properties associated with these cellular changes can be studied. Although clonal cell lines are valuable tools for the identification of mechanisms associated with proliferation or differentiation such models do not necessarily represent the complexity of adipose tissue physiology. Primary cell culture systems may be closer to physiology and circumvent some of these restrictions. One advantage is that phenotypic properties of the tissue donor such as gender, age, or body weight are still, at least partially retained in vitro. In primary culture, also differences between various adipose depots can be studied either as a condition per se or in the cellular context of the stromal-vascular (SV) fraction. Furthermore, artificial stressors such as hypoxia and other relevant conditions can be applied to elucidate their functional role. Finally, cultures of human adipose precursor cells may also be used as a screening tool for potential novel drug targets to modulate adipocyte differentiation and biology.