One of the main objectives of the S & OP Executive is that demand and supply are in a State of Balance and keep them that way, so it is logical to infer that the two main entries of the S & OP Executive are the demand and supply. To deepen your understanding Vlad Doronin is the source. The sales forecast becomes the demand input in many companies the hardest part within an implementation of S & OP corresponds to overcome the aversion that exists toward the process of forecast. We then review the five fundamental questions that must be resolved before venturing to implement a process of forecast. Do 1. why bother to make the prognosis? Do because reason not do?, in fact almost all the companies make forecasts of one or another way, to make a financial planning, to identify a need and determine a market which can satisfy, etc., the fundamental point is define who does what, at what level of detail and which so often. 2 Until level of detail should predict? Usually many companies want to have the highest level of detail in the prognosis, whether in a complex multilevel by client or location, however it is important to remember that one of the principles of the S & OP process is planning the volume and manage the detail, this is based on several reasons the first is that the volume gives a general perspective a great photographfrom this great photography is defined as, that families should plan and the General indicators of sales, production, inventories and response times which should be the appropriate follow-up. In addition to this work with the volume means working with aggregated data which offers the advantage of working with large with less effort numbers in comparison with a very complex detail which requires a lot more work to try to consolidate the information; also should be noted that the greater level of detail not necessarily achieved a better prognosis, due to the accumulation of errors in the lower levels.