This part of ISO 13053 describes a methodology for the business improvement process known as Six Sigma. The methodology typically comprises five stages: define, measure, analyse, improve and control (DMAIC). This part of ISO 13053 recommends the preferred or best practice for each of the stages of the DMAIC methodology used during the execution of a Six Sigma project. It also recommends how Six Sigma projects should be managed and the roles of personnel involved in such projects. It is applicable to organizations using manufacturing processes as well as service and transactional processes.