The invention provides methods and compositions for inducing brown fat cell differentiation through modulation of both Prdm1β and C/EBPβ activity and/or expression. Also provided are methods for preventing or treating obesity or an obesity related disorder in a subject through stimulation of both Prdm1β and C/EBPβ expression and/or activity. Further provided are methods for identifying compounds that are capable of modulating both Prdm1β and C/EBPβ expression and/or activity.