Scientists have investigated the fragile-to-strong transition of water. Unlike most liquids, when water is cooled, the rate of increase of its viscosity reaches a maximum at a certain low temperature. The team showed that modeling water as a temperature-dependent mixture of two states — disordered ‘fast’ water and locally ordered ‘slow’ water — explained the fragile-to-strong transition and avoided the faulty predictions of earlier theories based on glassy behavior.