Before embarking on the design of a modern shearer many aspects must be taken into consideration which will demand a substantial investment in time, resources and money. To be successful it is essential that the design requirements are established at the outset from study of the precise market requirements. The market will dictate the design in terms of need; seam application - thin, medium, or thick; particular trends and fashions of the time; available technology and the state of the art of associated equipment such as supports and AFCs.