From the perspective of a supplier high competitive pressure leads to considerable demand uncertainty and the need to guarantee availability of supply even for short-term peaks in demand at lowest costs. This problem determines the objectives of operative production planning as well as control, and thus the subject of this thesis. To achieve the objectives a three-part proactive method is developed. Part one concerns the design of a scenario generator for situational derivation of the demand uncertainty. For this purpose, all order histories are examined with regard to different regularities. The information obtained provide at each time of planning the groundwork for classification based calculation of alternative demand scenarios. In the second part of the developed method, profit-maximizing lot-size, sequence and capacity decisions are made based on a formal model and under consideration of the scenarios. Here, numerous practical requirements concerning the specific capacity of given elementary factors have been complied with. The final part of the solution integrates the scenario generator and the planning model in a control process to account for the dynamic planning environment. The concept was implemented as a prototype and evaluated by basic applications. It was shown that a significant increase of profit compared to a purely reactive approach is possible. In terms of low capital commitment a general increase of stocks is avoided.