In this paper, we adress the decision process of dynamically planning a product-based supply chain. We propose a linear program which minimizes operating costs and plans material flows in the supply chain over a rolling horizon. The result of the model is used to define long mid and short terms contracts with suppliers, subcontactors, business units and transporters. The supplying contracts take the form of periodic buying guarantees to be respected over a specific contract duration. This approach has been identified in the literature as being one way of constructing win-win relationship in a supply chain. A simple application of the model is provided.