Buffer management is not of a great concern when there is a perfect match between demand and supply. Demand represents the requirement for resources, and supply represents the collective capability of the resources to fulfill the requirements. A perfect match would then represent that supply can fulfill demand without any buffers involved, such as materials prepared in advance or capacity not being fully loaded. Such a perfect match is usually not possible to achieve since demand is frequently difficult to predict and the agility of the supply is limited. As a consequence, supply cannot perfectly match demand which may result in insufficient delivery performance. Different types of buffers may be employed to improve performance but they should only be used when the contribution of a buffer is greater than the cost of it. Hence, management of buffers is an important part of manufacturing planning and control (MPC) in order to mitigate such imbalances in pursuit of a competitive supply. The purpose here is therefore to define a framework for MPC that reflects the significance of buffers. To actually establish competitive supply is a complex challenge and four management perspectives are identified to support the balancing of supply with demand. Buffer management is here defined based on the intersection of these four management perspectives related to the transformation flow: the resources employed in the flow, the risk involved in the flow, the decision making related to the flow, and finally the planning and control to balance the flow.