The user anticipates mining requirements & specifies them in the form of Knowledge Discovery Schema during the planning phase. With the clear understanding of the domain & the mining requirements, the user guides the mining process. The type of knowledge to be mined, the database to be mined, the transformation to be done, cleaning procedure to be used, the specific mining algorithm to be run & finally the presentation tools to be used are specified by the user. These specifications can be entered through Knowledge Discovery Schema Editor or written directly in Knowledge Discovery Schema Language. The main issue at this level is the design of a comprehensive Knowledge Discovery Schema Language to communicate the mining requirements to the KDD process.