The document discusses keys to sustainability for multi-site operations. It identifies challenges such as a lack of strategic planning and poor energy monitoring. An effective approach involves implementing a structured energy management system (EnMS) based on the ISO 50001 standard. This includes setting up an energy monitoring system (EMS) to collect in-house data and establish a structured approach through the Plan-Do-Check-Act cycle. Continuous monitoring of energy performance is also essential to sustainability. The document provides examples of how to set up a blanket EMS model for multiple sites and the steps to implement energy performance services.