The general problem of stability under dead loading is treated for a body of any shape, the material being workhardening and rigid-plastic. It is shown that when the plastic potential and yield function coincide it is only necessary to examine in detail those neighbouring positions which can be reached by strain paths beginning as virtual modes of the yield-point state under the given loading. The least energy dissipated in passing to any such position has to be determined in constructing a sufficient condition for stability. The functional concerned turns out to be identical with that in the uniqueness condition for the typical boundary-value problem. On the other hand, the classes of admissible functions are different, so that failures of uniqueness and stability need not coincide; this is illustrated by the compression of a strut.