The development of plastic strain is followed from the elastic through the partially plastic to the fully plastic condition for a nonstrainhardening material. Adjacent to the zone of deformation in the fully plastic case is a region of limited plastic deformation. The growth of the plastic zone is compared with predictions based on the elastic-plastic solution for a semi-infinite solid and the elastic solution for a plate. Agreement is good at low stress levels. At high stress levels, a relatively simple semiempirical equation is proposed. Predictions based on elasticity theory alone are shown to be seriously in error.