A SIPOC diagram is a high-level map of a process, summarized in five columns: Suppliers, Inputs, Process, Outputs, and Customers. It captures who supplies what, the handful of steps in the middle, what comes out, and who receives it, all on one page. SIPOC is a staple of Six Sigma and process improvement, used to define and scope a process before detailed mapping.

SIPOC stands for Suppliers, Inputs, Process, Outputs, and Customers, read left to right. Suppliers provide the inputs, the process turns inputs into outputs, and customers receive those outputs. The order matches the flow of work through the process, which is why the columns sit in that sequence even though most teams fill the Process column in first.

Begin with the Process column: list five to seven high-level steps, no more. Then work outward. Name the outputs the process produces and the customers who receive them, then the inputs it needs and the suppliers who provide them. Starting in the middle keeps the steps high level and stops the map from turning into a detailed flowchart too early.

Use a SIPOC at the start of a process-improvement or Six Sigma project, in the define phase, when the team needs a shared picture of what a process covers. It's also useful when onboarding people to a process, or when a discussion keeps drifting because nobody agrees where the process begins and ends. It sets scope before any detailed work.

A SIPOC is the wide shot: five columns and a handful of high-level steps, enough to agree what a process covers and who's involved. A process map is the close-up: every step, decision, and handoff drawn in sequence. Teams usually build the SIPOC first to set scope, then expand its Process column into a full process map.