A ‘cheater’ mutation (chtB) in Dictyostelium discoideum, a free living slime mould able to co-operate as social organism when food is scarce, allows the cheater strain to exploit its social partner, finds a new study. The mutation ensures that when mixed with ‘normal’ Dictyostelium more than the fair share of cheaters become spores, dispersing to a new environment, and avoiding dying as stalk cells.