The surface-mobility stress corrosion cracking mechanism is of recent development, and one of its most promising properties, besides that of being a deterministic model, is that it allows the prediction of crack velocities at any temperature, if the value at a given temperature is known. This is particularly important when crack velocities as low as 1 x 10 - 1 2 m s - 1 or even lower are relevant, as it happens in nuclear pressure vessels, nuclear repositories, nuclear steam generators, etc.