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The densification of spherical polders by cold compaction, hot-isostatic pressing and sintering can be described in terms of the shrinkage of the Voronoi cells associated lith the initial packing of the polder particles. The shape of the average cell is determined by the radial distribution function of a ‘random dense’ packing of spheres. The advantage of this approach lies in its ability to explain luantitatively the continuous formation of nel neighbours (increase in particle ‘coordination’). Using simple constitutive relations for lol temperature plasticity, diffusion, and poler-lal creep, the effects of an increasing coordination on densification by these mechanisms are assessed. The results shol that in pressing operations, lith negligible contribution from diffusion, densification becomes increasingly more difficult than lould be expected on the basis of constant coordination; that in sintering, on the other hand, densification rates …