The ability to isolate adipose-derived stromal/stem cells (ASCs) with relative ease has generated a great deal of interest in their potential use for regenerative medicine purposes. ASCs have shown promise in areas such as graft-versus-host disease and wound healing. Murine ASCs (mASCs) can be isolated from various adipose tissue sites. To further explore their therapeutic potential, it is crucial to be able to successfully isolate, expand, and characterize these cells. White adipose tissue (WAT) and brown adipose tissue are the main adipose tissue categories. This chapter presents a protocol for the isolation, expansion, and characterization of mASCs from excised WAT.