Abstract: The present invention provides methods for producing cell populations enriched for stable, regulatory T cells (Tregs). In particular, the invention relates to methods for culturing T cells such that the final culture is enriched for stable, regulatory T cells. It also relates to methods for stabilizing regulatory T cells. Also provided are compositions enriched for stable, regulatory T cells, which are useful for treating individuals in need of such treatment. The methods and compositions disclosed herein can also be used to treat an individual suffering from an immune-mediated disease.