Book excerpt: Modern manufacturing systems must be engineered as any other complex systems, especially in the context of their integration. The book first presents the all-embracing concept of the Extended Enterprise as way of inter-enterprise integration. It then focusses on Enterprise Engineering methods and tools to address intra-enterprise integration using a model-based approach. Business process modelling and re-engineering isssues are particularly discussed and tools presented. Formal specification and Petri net-based analysis methods for manufacturing systems complete the set of tools for Enterprise Engineering. Coordination and integration issues of manufacturing systems and their business processes are then covered and examples of integration platforms presented. Finally, standardization and pre-standardization issues related to enterprise modelling and integration conclude the book.