In 1988, Motorola Corp. became one of the first companies to receive the Malcolm Baldrige National Quality Award. The award strives to identify those  excellent firms that are worthy role models for other businesses. One of Motorola's innovations that attracted a great deal of attention was its Six Sigma program. Six Sigma is, basically, a process quality goal. As such, it falls into the category of a process capability (Cp) technique.

The traditional quality paradigm defined a process as capable if the process's natural spread, plus and minus three sigma, was less than the engineering tolerance. Under the assumption of normality, this translates to a process yield of 99.73 percent. A later refinement considered the process location as well as its spread (Cpk) and tightened the minimum acceptable so that the process was at least four sigma from the nearest engineering requirement. Motorola's Six Sigma asks that processes operate such that the nearest engineering requirement is at least plus or minus six sigma from the process mean.

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