Six Sigma is a data driven process improvement methodology based on DMAIC project management cycle (Define-Measure-Analyze-Improve-Control).
It was first applied in manufacturing and it is currently used across all business sectors, including telecommunications, financial services, logistics, human resources and public services.
Here is an example of successfully using Six Sigma to satisfy and even exceed Critical Customer Requirements (CCRs), related to resolution of a customer request in a telecom vendor technical support centre (TSC).