Six Sigma is a philosophical approach to business that focuses on improving critical features of business products and service to near zero defects. Technically, the term Six Sigma is related to the instantaneous process capability of the product or service feature. When Six Sigma process capability is achieved, even with nominal process variation over time, the process only yields about 3.4 defects per million opportunities.

The process for achieving Six Sigma represents a new paradigm in business problem solving. It couples the use of traditional quality problem solving tools with the power of computer-assisted analysis to enable the entire business team to improve critical customer related outputs.

As a business improvement methodology, Six Sigma must accomplish two goals:

1. Improve the quality of vital customer related goods and services.
2. Contribute value to the corporate bottom line.

The methodology addresses the first goal by assuring a strong customer focus in the problems being worked on by the team. It addresses the corporate profitability goal through productivity gains achieved through significant defect reduction and improvement sustainability.

Significant defect reduction and sustainability are gained by focusing problem solving on understanding vital process inputs and leveraging them to improve process output. Once the improvement is made, ongoing process control includes controlling the input rather than just the output.

Motorola initiated the Six Sigma approach to process improvement in the early 1980's in response to weak acceptance of their product lines and dwindling market share. As a direct result of Six Sigma, Motorola gained a dominant share of the pager market and won the Malcolm Baldrige award in 1988. Many companies have adopted the Motorola approach in the 1990's, including Allied Signal, Bombardier, Eastman Kodak, General Electric and Honeywell.

General Electric adopted the Motorola approach, but then expanded that approach to include not just product related processes, but all of GE's critical processes, including a broad range of services. This success has enabled GE to grow operating margins to previously unheard of levels, even for them.