The fate of most cells in the mammalian thymus, namely CD4+CD8+ (double positive) cortical cells, is unknown. A fraction of the cells in this population serve as developmental intermediates, but the vast majority will die. In this article Ellen Rothenberg discusses how and when the cells are condemned or promoted to maturity, in the light of intriguing new data that suggests that they may be able to be rescued for longer than was previously thought.