The Mouse Embryonic Stem Cell Adipogenesis Kit provides a system designed for the differentiation of mouse ES cells into adipocytes. The kit contains all reagents necessary to differentiate mouse ES cells into Oil Red O positive adipocytes in vitro: (1) Gelatin Solution for proper support for cell attachment and spreading, (2) Accutase solution for the detachment of cells, (3) EB Formation Medium, a specially formulated medium that has been optimized and qualified to support the formation of embryoid bodies, (4) Inducer A Solution, (5) Insulin Solution and 3,3′,5-Triiodo-L-thyronine (T3), two hormones that aid in the differentiation of mouse ES cells to adipocytes, (6) Oil Red O Solution, a positive stain for adipocytes, and (7) Wash Solution and Dye Extraction Solution, both used to help quantify Oil Red O positive adipocytes using a spectrophotometer.