The Six Sigma Handbook, Revised and Expanded, 2nd Edition

1.1. WHAT IS SIX SIGMA?

This section provides a 10,000 foot overview of Six Sigma. Subsequent sections elaborate and provide additional information on tools and techniques.

Six Sigma is a rigorous, focused and highly effective implementation of proven quality principles and techniques. Incorporating elements from the work of many quality pioneers, Six Sigma aims for virtually error free business performance. Sigma, σ, is a letter in the Greek alphabet used by statisticians to measure the variability in any process. A company's performance is measured by the sigma level of their business processes. Traditionally companies accepted three or four sigma performance levels as the norm, despite the fact that these processes created between 6,200 and ...