A SIPOC diagram identifies all elements of a process improvement project before work begins. It helps define the scope of a complex project by answering questions about where the process starts and ends, its major steps, inputs and outputs, key customers and suppliers, and customer requirements. The diagram provides a deep understanding of the current process. It typically includes suppliers, inputs, process steps, outputs, and customers. Metrics may also be included to define quality, time, and cost of inputs, processes, and outputs. The diagram helps scope and plan a process improvement project.