The information infrastructure – comprising computers, embedded devices, networks and software systems – is vital to operations in every sector: chemicals, commercial facilities, communications, critical manufacturing, dams, defense industrial base, emergency services, energy, financial services, food and agriculture, government facilities, healthcare and public health, information technology, nuclear reactors, materials and waste, transportation systems, and water and wastewater systems.  Global business and industry, governments, indeed society itself, cannot function if major components of the critical information infrastructure are degraded, disabled or destroyed. Critical Infrastructure Protection XII describes original research results and innovative applications in the interdisciplinary field of critical infrastructure protection.  Also, it highlights the importance of weaving science, technology and policy in crafting sophisticated,yet practical, solutions that will help secure information, computer and network assets in the various critical infrastructure sectors.  Areas of coverage include: Themes and Issues; Infrastructure Protection; Infrastructure Modeling and Simulation; Industrial Control Systems Security. This book is the twelfth volume in the annual series produced by the International Federation for Information Processing (IFIP) Working Group 11.10 on Critical Infrastructure Protection, an international community of scientists, engineers, practitioners and policy makers dedicated to advancing research, development and implementation efforts focused on infrastructure protection.  The book contains a selection of fifteen edited papers from the Twelfth Annual IFIP WG 11.10 International Conference on Critical Infrastructure Protection, held at SRI International, Arlington, Virginia, USA in the spring of 2018. Critical Infrastructure Protection XIIis an important resource for researchers, faculty members and graduate students, as well as for policy makers, practitioners and other individuals with interests in homeland security.