The Independent Electricity System Operator (IESO) works at the heart of Ontario’s power system to ensure that there is enough electricity to keep the lights on, today and into the future. We operate the power system in real time, oversee Ontario’s electricity markets, deliver energy efficiency and plan for Ontario’s future energy needs. In today’s fast-changing energy landscape, ensuring Ontario’s businesses and communities have access to reliable and affordable power is becoming more complex – and more exciting.