CMMI with Agile, Lean, Six Sigma, and Everything Else



Mike Phillips

This library item is related to the following area(s) of work:

Process Improvement

This article was originally published in News at SEI on: January 1, 2008

I repeatedly encounter those seeking the one solution that will solve the problems in their organization. Such a search is often commissioned by a boss who wants the single answer and a quick fix to the organization’s problems. In this column, I try to describe how to relate some of these answers rather than trying to make any of them—even CMMI—a single solution.

The Choices

There are a wide range of improvement approaches that are often mentioned as the solution to problems confronting organizations that recognize a need to improve. For years, various standards and modelscaptured principles for process improvement, often called best practices. ISO 15288 and ISO 12207 are likely standards that are familiar to you if you are faced with complex, software intensive systems development. In addition to the collection of CMM and CMMI models, collections of other models such as the Project Management Institute’s Organizational Project Management Maturity Model (OPM3) and Control Objectives for Information and related Technology (CoBIT) are also likely familiar to many of you.

Others interested in process improvement investigated the best practices in these and other models and standards and found ways to capture some of these principles into methods that accomplish a process, such as software system development. Examples of current software development methods include Agile methods, Scrum, and the SEI’s Team Software Process (TSP) methodology. Those of you who are past the major development stage and are more concerned about maintaining information-technology capabilities are likely familiar with collections of methods for service related activities such as the Information Technology Infrastructure Library (ITIL).

To add another layer of complexity, there are also improvement techniques that apply in various domains and disciplines. Three current representative techniques are Lean, Six Sigma, and Theory of Constraints. One way to relate the principles, methods, and techniques discussed thus far is depicted below in Figure 1. I’ll spend the remainder of this column discussing some of the relationships and synergies that makes the search for the best one a limiting strategy.

Figure 1: Principles, methods, and techniques

Figure 1: Principles, methods, and techniques

How do these improvement elements relate?

Figure 1 is an attempt to aid the discussion of these fundamentally different groupings of principles, methods, and techniques as interrelated improvement elements. Typically, models and standards provide high-level information about reasonable frameworks for a discipline, such as engineering or project management, or a major effort, such as development or acquisition.

If we use CMMI for Development (CMMI-DEV) as a familiar example, we suggest that many approaches to development can be taken within the broad framework represented by the content of CMMI-DEV. Methods, then, can perhaps best be thought of as ways actually to do the work—the “how” that the “what” of the models may not adequately address. The best example we have of an effective method linked to CMMI-DEV is TSP. Similarly, Agile methods also fit within a model structure such as CMMI-DEV. Like TSP, Agile methods seek to provide detailed approaches to development tasks.

The figure illustrates a vertical collection of techniques that represent a different direction or dimension of improvement elements. These techniques can investigate and solve problems in organizations. Three that have been called out by the Department of Defense for process improvement are Lean, Six Sigma, and Theory of Constraints. (Often the first two are combined into a single approach now described as Lean Six Sigma.) These techniques are depicted as vertical approaches because they allow disciplined ways both to improve how particular task elements are performed as well as to provide broad deployment approaches.

Apples and Oranges

When you are searching for a silver bullet to solve your organizational challenges, the truth is that there is no one-size-fits-all answer. The choices you need to make are actually quite different. Each example in the figure has proved its value in improving elements of various organizational challenges. However, some of these approaches fit better in specific organizational cultures or professional disciplines. I observed one large company in which one unit was actively engaged in CMMI-based process improvement. Its sister division, about two blocks away, was equally committed to its Six Sigma investment, with many black belts and green belts on staff. However, the two divisions could not seem to share their lessons learned. As many organizations have learned, Six Sigma is a powerful improvement technique within a CMMI framework. So this particular company had not yet seen the synergistic value of teaming a model and a technique.

How about choices between models and standards?

As much as I love our CMMI Product Suite, I recognize that there are other valuable views of the enterprise that also stimulate improvement and a strong commitment to quality. Many of you are familiar with the chart I use to suggest coupling ISO 9000 with CMMI [Figure 2]. And most of you are aware that the CMMI Product Development Team has encouraged mappings of CMMI with various other models and standards to facilitate using them together. Some of these mappings can be found at in the CMMI section of our site. The SEI has initiated a more extensive effort to investigate effective ways to perform multiple-model approaches to process improvement, and is seeking sponsors and researchers for this area of interest.

 Figure 2: Coupling ISO 9000 with CMMI

Figure 2: Coupling ISO 9000 with CMMI

Is it best to pick one model, one method, and one technique?

Most of us live in a multi-disciplinary world and we want to improve both our basic work practices and our organizational process discipline. Creating an effective mix of models and methods, with selected techniques to troubleshoot specific challenges, appears to have a high return on investment.


In the beginning, CMMI was developed as an effort to consolidate engineering best practices. Now we need to continue expanding the capabilities of our users without growing the size of the models by improving the interoperability of CMMI with its peers in the process improvement domain. While we feel that the CMMI Product Suite provides a valuable foundation for guiding process improvement choices for the enterprise, we feel that deploying effective operating methods in the domain and using improvement techniques under a CMMI umbrella can maximize the improvement of developing, deploying, and supporting our software intensive, knowledge-based systems.

About the Author

As the director of special projects at the Software Engineering Institute, Mike Phillips leads the Capability Maturity Model Integration (CMMI) project for the SEI. He was previously responsible for transition-enabling activities at the SEI. Prior to his retirement as a colonel from the Air Force, he managed the $36B development program for the B-2 in the B-2 SPO and commanded the 4950th Test Wing at Wright-Patterson AFB, Ohio. In addition to his bachelor’s degree in astronautical engineering from the U.S. Air Force Academy, Phillips has master’s degrees in nuclear engineering from Georgia Tech, in systems management from the University of Southern California, and in international affairs from Salve Regina College and the Naval War College.

Please note that current and future CMMI research, training, and information has been transitioned to the CMMI Institute, a wholly-owned subsidiary of Carnegie Mellon University.

Find Us Here

Find us on Youtube  Find us on LinkedIn  Find us on twitter  Find us on Facebook

Share This Page

Share on Facebook  Send to your Twitter page  Save to  Save to LinkedIn  Digg this  Stumble this page.  Add to Technorati favorites  Save this page on your Google Home Page 

For more information

Contact Us


Help us improve

Visitor feedback helps us continually improve our site.

Please tell us what you
think with this short
(< 5 minute) survey.