A conceptual model for the application of Six Sigma methodologies to supply chain improvement

Abstract

This paper hypothesises that, whilst Six Sigma as a change and improvement strategy is delivering significant business benefit to practitioner organisations, it has not been successfully adapted to deliver similar benefits across supply chains. It demonstrates by reference to the literature that most published applications of Six Sigma in supply chains are related to the application of traditional internal Six Sigma methodologies to the internal processes of a supplier to the “Six Sigma Organisation”. In this paper, the issues particular to an application of Six Sigma in a broader supply chain context are discussed, with reference to specific supply chain issues. It is concluded that Six Sigma does have something novel to offer organisations over and above the contribution of existing approaches to supply chain improvement, and a conceptual model is proposed that is consistent with the literature and has potential to support such an introduction. The model integrates the Balanced Scorecard, SCOR model (Supply Chain Reference model) and Six Sigma DMAIC (define, measure, analyse and improve) methodology in a two-level framework. This is a strategic-level cycle, developing focused projects to generate maximum business benefit, and an operational-level cycle, applying Six Sigma and lean tools in a DMAIC cycle to deliver supply chain improvements. Cautions and requirements for the success in practice of such a model are discussed and it is concluded that the model should be tested in practice to validate and develop further the methodology.

Keywords:

• Six Sigma
• Supply chain improvement
• Lean
• SCOR model
• Variability reduction