Economic and social stability across the world is tightly dependent on a sufficient and reliable flow of goods and services, based on the balance between supply and demand. The basis for the balance between supply and demand is a set of physical assets, processes and organisations that are collectively known as critical infrastructure systems (CIs). CIs are strongly interdependent in two complex ways: namely, physical and informational. Identification of CI interdependencies and interconnections is essential for the study of such supply and demand systems. Importantly, CI interdependencies and interconnections are also essential for the development of models that help in the study of the impact of extreme events or disasters, or prediction of economic loss from damage caused by cascading impacts on the supply and demand chain system. Based on the stated problem, the aims of this research can be summarized as an estimation of economic loss. This estimation includes individual industry loss and total economic loss, taking interconnected industries into consideration. The main aims are to develop and test a new model and to develop a methodology based on this model for the assessment and management of risk from extreme events on critical infrastructure systems.