Satisfactory agreement has now been obtained between the MHD model and the experimental behaviour of a plasma focus. On the basis of this agreement and similarity theory, the authors formulate various sets of predictions relating to a device with a high energy content. The authors discuss the different sets of predictions and estimate the associated degree of uncertainty. The relationship, derived from extrapolation of the theoretical results, between neutron yield and capacitor bank energy is confirmed experimentally by increasing the latter several times.