The paper reviews the different components of settlement and essential concepts of undrained creep of saturated clays. The results of triaxial and simple shear undrained creep tests on a Norwegian clay are compared to the results reported in the literature. The undrained characteristics are assembled in a creep susceptibility diagram and analysed as a function of the behaviour of other materials known to be creep susceptible. A procedure to estimate the creep susceptibility of a clay in practice is proposed.