Modern systems fail in ways that are hard to trace. Slow queries, blocked sessions, memory pressure, unstable integrations, and reporting workloads often overlap. Many teams respond with guesswork, which leads to partial fixes and more confusion. This session shows a structured way to diagnose performance problems using Systems Thinking and proven engineering practices. You will see how to read the signals from SQL Server, how to track production bottlenecks, how to separate workloads that compete for resources, and how to connect symptoms across services. Real examples from ERP, APIs, and reporting systems illustrate common patterns and failure modes. Attendees walk away with a repeatable process to find root causes faster, improve stability, and reduce stress during incidents.