A process’ sigma is a statistical measure that designates its capability to deliver defect free results. At 3 sigma, a process works as expected in 93% of the instances.		"In 6 sigma, a process performs as expected in 99.9997% of the instances"

Behind those numbers lie significant inefficiencies, ‘hidden factories’ (unnecessary work), many dissatisfied customers, and a tremendous productivity and customer satisfaction opportunity. Quality related costs for
a 3-4 sigma company are estimated at about 10-15% of its revenues.

Six Sigma looks at improving process performance through the measurement of its capabilities and the statistical analysis of the factors that contribute to its output. It follows the DMAIC process:		"Six Sigma uses data to profoundly understand customer needs and process behaviour, and employs robust improvement methodology to improve those processes"

Define		Quantitatively define the customer’s needs. Define the scope of the process that will be tackled and the specific improvement objectives.
Measure		Measure the process performance against customer needs.
Analyse		Analyse the performance data and study the process to identify the key factors that contribute to the process output.
Improve		Propose and statistically test process improvements.
Control		Set-up controls to ensure the improved process performance and factors that contribute to it remain stable.

As a methodology, Six Sigma is customer centric and data based. As an improvement program, it is project focussed and results oriented – a continuum of selected high impact process improvement projects executed by Black Belt (Six Sigma specialists) led teams in short timeframes of 4-5 months, and with measurable results.