Beige adipocytes residing within white adipose tissue burn fuels to generate heat by a process called thermogenesis. Therapeutic induction of beige adipocytes may be able to be harnessed to reduce obesity by burning rather than storing excess fuels. Cells of the immune system – including eosinophils –appear to be essential in the beiging of white adipocytes. Using a genetic mouse model, we recently uncovered gene regulatory mechanisms in mice that allow adipose tissue eosinophils to secrete molecules important for beige fat activation and prevention of weight gain. We are now testing whether novel secreted proteins we have identified are able to induce beiging and energy expenditure and may present novel targets for obesity. We are also exploring how the gene expression programs in adipose tissue-resident eosinophils differ from eosinophils residing in other tissues in the body and the transcription factors that drive this niche specification.