The safe management of the complex distributed systems and critical infrastructures which constitute the backbone of modern industry and society entails identifying and quantifying their vulnerabilities to design adequate protection, mitigation, and emergency action against failure. In practice, there is no fail-safe solution to such problems and various frameworks are being proposed to effectively integrate different methods of complex systems analysis in a problem-driven approach to their solution.

Vulnerable Systems reflects the current state of knowledge on the procedures which are being put forward for the risk and vulnerability analysis of critical infrastructures. Classical methods of reliability and risk analysis, as well as new paradigms based on network and systems theory, including simulation, are considered in a dynamic and holistic way.

Readers ofVulnerable Systems will benefit from its structured presentation of the current knowledge base on this subject. It will enable graduate students, researchers and safety and risk analysts to understand the methods suitable for different phases of analysis and to identify their criticalities in application.

Prof. Dr. Wolfgang Kröger works in the Mechanical and Process Engineering Department at ETH Zurich, Switzerland.

Enrico Zio (BS in Nuclear Engineering, Politecnico di Milano, 1991; MSc in Mechanical Engineering, UCLA, 1995; PhD in Nuclear Engineering, Politecnico di Milano, 1995; PhD in Nuclear Engineering, MIT, 1998) is Director of the Chair in Complex Systems and the Energetic Challenge of Ecole Centrale Paris and Supelec, full professor of Reliability, Safety and Risk Analysis at Politecnico di Milano, Rectors delegate for the Alumni Association of the Politecnico di Milano, adjunct professor in Risk Analysis at the University of Stavanger, Norway and at Universidad Santa Maria, Chile, and invited lecturer and committee member at various Masters and PhD programs in Italy and elsewhere. He is the past Director of the Graduate School of the Politecnico di Milano

He is the current Chairman of the European Safety and Reliability Association (ESRA), which he has previously served as Vice-Chairman (2000-2005).

He has also served as Editor-in-Chief of the international journal Risk, Decision and Policy (2003-2004) and is a member of the Korean Nuclear Society and China Prognostics and Health Management Society.

He is a member of the editorial boards of the international scientific journals Reliability Engineering and System Safety, Journal of Risk and Reliability, Journal of Performability Engineering, Journal of Science and Technology of Nuclear Installations, plus a number of others in the reliability, safety and nuclear energy fields.

1. Introduction and Definition of Key Terms.- 2. Properties of Critical Infrastructures.- 3. Challenges to Methods for the Vulnerability Analysis of Critical Infrastructures.- 4. Basic Approaches.- 5. Conceptual Frameworks for Vulnerability Assessment.- 6. Methods of Analysis.- 7. Concluding Considerations.