An understanding of the properties and the handling characteristics of liquids and gases has long been regarded as an essential requirement for most practising engineers. It is therefore not surprising that, over the years, there has been a regular appearance of books dealing with the fundamentals of fluid mechanics, fluid flow, hydraulics and related topics. What is surprising is that there has been no parallel development of the related discipline of Bulk Solids Handling, despite its increasing importance in modern industry across the world. It is only very recently that a structured approach to the teaching, and learning, of the subject has begun to evolve. A reason for the slow emergence of Bulk Solids Handling as an accepted topic of study in academic courses on mechanical, agricultural, chemical, mining and civil engineering is perhaps that the practice is so often taken for granted. Certainly the variety of materials being handled in bulk is almost endless, ranging in size from fine dust to rocks, in value from refuse to gold, and in temperature from deep-frozen peas to near-molten metal.