Critical Infrastructure Interdependencies

Tyson Macaulay’s work on Critical Infrastructure Interdependencies (CII) reminds us that Canada’s critical infrastructure is complex and deeply interconnected. Our infrastructure spans ten sectors, multiple provinces and territories, public and private ownership models, and layered governance structures. No sector operates alone. Energy supports telecommunications; telecommunications support finance; transportation supports supply chains and emergency response. When one system is disrupted, impacts can cascade quickly across others.

CII goes beyond individual sectors. It spans the four interconnected domains of critical infrastructure, national security, emergency management, and defence. Cyber and physical systems are intertwined, and risks in one area can create consequences in another. Understanding these interdependencies is essential for prioritizing assets, strengthening resilience, and improving threat and risk assessments.