Cyber attacks have the potential to pose a systemic risk by disrupting the business operations of key participants in Canada’s financial system. The operational resilience of these participants—large financial institutions and the financial market infrastructures (FMIs) they participate in—is central to the overall resilience of the financial system The attackers targeting elements of Canada’s financial system are a diverse group, with varying levels of sophistication and capabilities. Canadian financial institutions and FMIs have been proactive in building up their defenses against cyber attacks and actively collaborate with one another and with the federal government.