In the era of continuous changes in internal organizationalsettings and external business environments - such as new regulations and business opportunities - modern enterprises are subject to extensive research and study. For the understanding, design, and engineering of modern enterprises and theircomplexbusiness processes,thedisciplineofenterpriseengineeringrequires sound engineering principles and systematic approaches based on rigorous th- ries. Along with that, a paradigm shift seems to be needed for addressing these issues adequately. The main paradigm shift is the consideration of an enterprise and its business processes as a social system. In its social setting, an enterprise and its business processes represent actors with certain authorities and assigned roles, who assume certain responsibilities in order to provide a service to its environment. Second to that, a paradigm shift is to look at an enterprise as an artifact purposefully designed for a certain mission and goal. The need for this paradigm shift, along with the complexity and agility of modern enterprises, gives inspiration for the emerging discipline of enterprise engineering that requires development of new theories and methodologies. To this end, the prominent methods and tools of modeling and simulation play a signi?cant role. Both (conceptual) modeling and simulation are widely used for understanding, analyzing, and engineering an enterprise (its organization and business processes).

"This book constitutes the proceedings of the 5th International Workshop on Cooperation and Interoperability, Architecture and Ontology (CIAO!) and the 5th International Workshop on Enterprise and Organizational Modeling and Simulation (EOMAS) held at CAiSE 2009 in Amsterdam, The Netherlands, on June 8-9, 2009. The 14 papers presented were carefully reviewed and selected for inclusion in the book. CIAO! had 24 submissions and accepted 10 for publication, EOMAS had 21 submissions and accepted 8 papers of which 4 are included in this volume. The topics covered are modeling and simulation; enterprise architecture and governance; applications of enterprise engineering; and the dissemination and extension of DEMO (Design and Engineering Methodology for Organizations)."

Modeling and Simulation.- Method Versus Model - Two Sides of the Same Coin?.- Capturing Complex Business Processes Interdependencies Using Modeling and Simulation in a Multi-actor Environment.- A Heuristic Method for Business Process Model Evaluation.- Simulating Liquidity in Value and Supply Chains.- Enterprise Architecture and Governance.- Complexity Levels of Representing Dynamics in EA Planning.- An Approach for Creating and Managing Enterprise Blueprints: A Case for IT Blueprints.- An Information Model Capturing the Managed Evolution of Application Landscapes.- Enterprise Engineering - Applications.- A Service Specification Framework for Developing Component-Based Software: A Case Study at the Port of Rotterdam.- Enhancing the Formal Foundations of BPMN by Enterprise Ontology.- Developing Quality Management Systems with DEMO.- Analyzing Organizational Structures Using Social Network Analysis.- DEMO - Dissemination and Extension.- The Adoption of DEMO: A Research Agenda.- ArchiMate and DEMO - Mates to Date?.- Integration Aspects between the B/I/D Organizations of the Enterprise.