Process planning is one of the key activities for product design and manufacturing. Impact of process plans on all phases of product design and manufacture requires high level of interaction of different activities and tight integration of them into coherent system. In this paper we describe a model for manufacturing activities that allows such integration. The framework for integration is briefly described and the manufacturing process model that considers three dimensions of planning is explained. Some implementation issues of model are also discussed. Benefits of integrated consideration are described for several possible scenarios, such as product/process design, process planning/layout planning, process planning/scheduling. Manufacturing process model is described as three-dimensional model with the following dimensions: time/order, variability/altematives, and aggregation. All dimensions are defined and explained as they are related to overall manufacturing planning. The nature of these dimensions is illustrated with several examples. Process plan network is described as a part of manufacturing process model that allows integration by means of representing alternative process plans. This hierarchical network is embedded into manufacturing process model for process planning tasks. Dimensions of the model are identified within the network. Extension of the model for other activities is also discussed. The use of the model in dynamic process planning and methods for the model visualization are described.