Service Level Indicators (SLIs) are quantitative measures that evaluate the level of service provided by internal teams or service providers. They help maintain customer satisfaction and operational efficiency. There are six critical metrics for effective incident management: response time, error rate, service availability, system throughput, response latency, and compliance. Monitoring and optimizing these metrics help shape Service Level Agreements (SLAs) and ensure realistic agreements with users. The harmony between SLAs and SLIs leads to a well-run service operation and satisfied customers.