High temperature components made of metal/intermetallic and ceramic powders are increasingly being produced by hot isostatic pressing (HIP). In a typical HIPing process, powder is first packed in a thin-walled can of the desired shape, and placed in a furnace within a pressure vessel. Gas pressure is then applied, and the temperature raised. Powder is softened because of high temperature, and densification occurs by a combination of plasticity, power law creep and diffusional flow. Ideally, components with a uniform density distribution are sought, but in practice this sometimes is not achieved. Under some conditions powder near the hotter outer can surface densifies faster than the cooler interior, forming a denser outer skin that shields inner powder from pressure. Li, Ashby and Easterling have analyzed the mechanism in detail and interested readers are referred to (1).