We tested for predator-induced plasticity in development and growth of embryos and young tadpoles of green frogs (Rana clamitans). We expected to observe developmental plasticity in response to the leech, Macrobdella decora, because the leech represents a high, but unpredictable, risk of mortality. Embryos raised with a leech tended to delay hatching and hatched at larger size. Young tadpoles raised with a leech grew more slowly than tadpoles raised without a leech. Such changes should enhance survival of green frogs faced with the threat of leech predation.