An organization is getting into process improvement. Should it look at the Software Engineering Institute’s capability maturity model integration (CMMI) first? Six Sigma first? Or both at the same time?

This dilemma has confronted many organizations during the last several years. The situation reminds me of a session at a symposium in 1984 at which both W. Edwards Deming and Joseph Juran were present at the symposium. Someone from the audience asked, “Should we follow Deming’s teachings or those of Juran?” Deming, in his inimitable, gruff voice responded, “Pick either…just do something.”

While the same question could arise about the use of CMMI or Six Sigma, there have been some interesting case studies during the last few years surrounding the order of choice. Since I have spent 80 percent of my time during the last 15 years with SEI CMMI and its predecessor, the SW-CMM®, one would expect a bias in favor the CMM/CMMI. However, I have personally been associated with three case studies demonstrating the benefits of looking at Six Sigma first…at least a little bit first.

All three scenarios involved organizations that were well into the Six Sigma expansion. There were Black Belts, Green Belts and Champions trained. All staff had some form of Six Sigma orientation, at least a four-hour overview.

The three organizations were:

  • A medium-sized financial specialty company in the Midwest.
  • An IT organization of a large educational supplier in the Southwest.
  • A 120-person division of a multi-national communications vendor in the Southeast.

All had made significant inroads into Six Sigma’s DMAIC roadmap before they ventured into the SEI CMM/CMMI world. Each was introduced to the CMMI via training and consulting. After about two months, a “mini-assessment” (Class C appraisal) was held. The results across the board were significantly different than the usual initial appraisal. A significant number of processes were already documented and used, as opposed to the usual blank stares when procedures/templates are requested during an appraisal. All three had results more typical of a second or third round of appraisals than the normal results. Especially noticeable was the difference in the quantitative-based process areas (e.g., measurement and analysis at maturity level 2 and the maturity levels 4 and 5 process areas covering quantitative process management and formal continuous improvement). In most initial Class C appraisals, no one bothers to look at maturity levels 4 and 5 process areas, sometimes not even maturity level 3. In all three cases, plans called for reviewing only maturity levels 2 and 3. As the appraisals progressed, the results were so startling that the maturity levels 4 and 5 also were investigated.

In each of the three cases, the following areas are presented for summary comparison:

Case 1 Results

  • Measurement and analysis process area: All goals were satisfied with all practices implemented, and no improvement opportunities.
  • Maturity level 4 process areas (2): All but two goals were satisfied. All practices largely implemented with three improvement opportunities.
  • Maturity level 5 process areas (2): All but two goals satisfied. All practices largely/partially implemented with two improvement opportunities.
  • Follow-up accomplishments: The group completed a maturity level 2 appraisal as planned for calendar year objectives. The maturity level 3 appraisal was successful nine months later. Plans were halted when the organization was acquired by a large multi-national organization.

Case 2 Results

  • Measurement and analysis process area: All goals and practices compliant with one improvement opportunity.
  • Maturity level 4 process areas (2): All but two goals compliant. All practices largely / partially compliant with five improvement opportunities.
  • Maturity level 5 process areas (2): All but one goal compliant. All practices largely compliant with two improvement opportunities.
  • Follow-up accomplishments: The group was appraised at level 3 three months later and is planning for a level 5 appraisal this quarter.

Case 3 Results

  • Measurement and analysis process area: All goals and practices compliant with one minor improvement opportunity.
  • Maturity level 4 process areas (2): All but one goal compliant. All practices largely compliant with three improvement opportunities.
  • Maturity level 5 process areas (2): All goals and practices compliant.
  • Follow-up accomplishments: The group was appraised at level 3 one month later and level 5 six months following that event.

The above results are phenomenal for first-time Class C appraisals. Upon further investigation, all stakeholders agreed that the Six Sigma tools and mindset had contributed greatly to such unparalleled results. Also documented were such shared characteristics as:

  • All processes and procedures contained measurements, root cause analysis, and continuous improvement follow-up.
  • All organizational results exceeded the data published by the SEI benchmarking activities.
  • All levels of management and staff used the measurements on a daily basis.

More interestingly, all three of these case studies involved organizations whose Six Sigma training and focus had been strictly DMAIC. All three believe that their CMMI results as well as the organizational measurements would have been significantly better if their Six Sigma training had included the concepts in Design for Six Sigma, with more focus on understanding requirements and performance drivers versus the DMAIC fix-and-improve approach.

I am still a devout CMMI advocate. It is unmatched at providing the “whats” of process improvement and design. However, I am encouraged and impressed by the three cases investigated demonstrating the horsepower gained from a Six Sigma approach and mindset. I suspect that Drs. Deming and Juran would be pleased to see the gains they enabled via the tools and cultures of quality.

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