The very first Six Sigma book I read was The Six Sigma Way. The first page describesthe story of a CEO jumping to solutions and being educated by a Black Belt on the methodology. He is turned around and states, “We’re not in the ‘Just Do It’ mode anymore”. My take-away being, we take a disciplined and structured approach we improve the right things in the right way.

The lack of an official “Six Sigma” can mean different versions being taught. Overall I think there is broad agreement on the approaches and tools we use in Define, Measure & Analyse. Of course, the setting drives the specific tools we use (see What Flavour Are You). But if you are looking for variation take a look at Improve.

Over the years I have been using the ASQ Black Belt body of knowledge as the basis for my continual learning, working through subjects in my own time to ensure I really understand them. I have got to Improve andthere is a problem. Now the approach I was taught and deliver to our Green & Black Belts is to:

• Use creative thinking to develop a long-list of potential solutions
• Use convergent thinking to develop the optimal solution
• Establish and mitigate risks
• Run pilots and DoE to establish and prove solution achieves goal
• Develop implementation plan ready for toll gate

Reading through my now wide collection of books this is quite an orthodox approach with two exceptions. Firstly, the ASQ BoK I use describes Improve as below.

• Design of experiments
• Response surface methodology
• Evolutionary operations

I checked and the newest version now introduces Implementation Planning, Risk Analysis and the Lean concepts of Waste, TOC & Kaizen. Secondly my copy of Implementing Six Sigma covers:

• Design of experiments
• Response surface methodology
• Evolutionary operations

My guess is that the people who developed the ASQ BoK and “Implementing Six Sigma” must have collaborated and describe an Improve phase that is different to a number of other authors. There is no mention of the creative processes:-divergent thinking, six thinking hats, brain writing, or lateral thinking.

As a practitioner what it means to me is I learn both and decide which to apply and when. I am also updating mycopy of the ASQ BoK to the latest version.