Abstract
This paper is concerned with the definition of a feasible master schedule for operations management, obtained through an integrated planning system, using a hierarchical methodology (by means of different disaggregation stages) with an appropriate time horizon for connection with the manufacturing requirements planning unit (MRP II). The hierarchical model obtained considers not only product aggregation into types, families and items but also resources aggregation, structure of products aggregation or bill-of-materials aggregation, as well as temporary aggregation. It allows the creation of a master schedule for an adequate time horizon, that can be used as an