Synopsis Critical Infrastructure refers to those sectors of an economy which have direct impact on the functions and sustainability of the economy. It embraces material assets, facilities, industries and capabilities that are essential for the functioning and well-being of a society and economy. These days, due to global terrorism and increasing international political upheavals, nations the world over, face high security risks and need to instate an integrated and well-planned critical infrastructure protection system that assesses risks and plans for potential contingencies. After the attack on World Trade Centre, all the countries of the world have shown their concerns for identification, development, maintenance and protection of their critical infrastructure. Countries have their own priorities for deciding the infrastructures of critical importance. Poor countries have to compromise with their critical infrastructure on account of scarce resources, but the proper approach and planning in critical infrastructure can help those countries to balance their security needs and maintain the continuity, sustainability and feasibility of economic affairs. The criticality of the infrastructure can be observed from the economic consequences of various Pandemics such as Anthrax, SARS, plague, natural disasters like Tsunami and hurricane Katrina, the terrorist activities, cyber attacks, political unrest, wars and disturbances in public services. This book provides select readings on the concept of critical infrastructure, its assurance, protection and discusses the emerging issues from various critical infrastructure sectors.