This paper presents a method of analysing the effects of volume change in unsaturated expansive clays on engineering structures. The analyses are carried out using a finite element program with conventional non-linear elastic soil parameters as determined in existing laboratory techniques. These parameters can be obtained, for example, using modified suction controlled consolidometers now in common use together with isotropic pressure tests in pressure membrane apparatus. Some hypothetical analyses of slab-on- ground foundations indicate that the most critical design criteria, viz., differential displacements, are controlled mainly by the volume change characteristics of the soil and the rigidity of the concrete slab. The modulus of the soil and the slab are shown to have little effect. Comparisons with the slab-on-ground design technique were able to be made and while showing similar trends, the analyses used in this paper tended to be less conservative in the examples considered. (Author/TRRL)