Motorola introduced Six Sigma as a process-improvement method in 1986. The approach was developed by engineer Bill Smith while he was working at Motorola, where it focused on reducing manufacturing defects and process variation.
The name comes from statistical quality control: a process operating at six sigma is intended to keep outcomes extremely close to the target and within specification. Motorola made the method central to its quality program and later registered “Six Sigma” as a service mark in 1991.
Six Sigma became much more widely known after adoption by other major companies. General Electric, under CEO Jack Welch, made it a core business strategy in the 1990s, while Honeywell also became an important early adopter. Those later successes sometimes lead people to credit GE with inventing it, but Motorola pioneered the method and introduced it in 1986.
Modern Six Sigma commonly uses the DMAIC cycle—Define, Measure, Analyze, Improve, and Control—for improving existing processes. It is also frequently combined with lean manufacturing as “Lean Six Sigma.”