RIP140 is a ligand-dependent corepressor for most, if not all, nuclear receptors. It is expressed widely in many different tissues, but the phenotype of mice devoid of RIP140 indicates that it plays a crucial role in the ovary and in adipose biology. Ovarian expression of RIP140 is cell-type-specific during follicular development and it is essential for oocyte release during ovulation, but not for luteinization of mature ovarian follicles. In adipose tissue, RIP140 is essential for normal fat accumulation and RIP140-null mice show decreased lipid storage even on a high-fat diet, with upregulation of mitochondrial uncoupling protein (UCP1) in some fat depots. Thus RIP140 plays a crucial role in female fertility and in energy homeostasis, and could be a target for infertility treatment, new contraceptive strategies or prevention of obesity.