Each KPA includes a set of activities based on industry best practices for that area. In addition, the KPA describes the supporting infrastructure and activities to ensure the practices will be institutionalized. Thus KPAs are the building blocks for improving the processes of software development and software project management. The overall capability of an organization is captured in the concept of maturity and characterized by stages that reflect the degree of the organization's effectiveness at a point in time. The CMM characterizes these steps in its five levels of maturity.
Early levels are foundations to the later levels.
It is especially important to note that while each KPA includes a set of activities based on industry's best practices for that area, it does not dictate the exact processes themselves, allowing tailoring to account for individual business objectives, corporate culture, etc. This flexibility increases the chance of success significantly, if the program to implement the framework is thought through properly. Perhaps a good case study of adherence to CMM principles is Telcordia, which achieved CMM Level 5 about a year ago. Noting the industry change in the early'90s, Telcordia recognized that having error-free software was essential. In addition, its customers were demanding that the software development cycle be shortened considerably so that they could respond more quickly to the needs of the constantly changing marketplace.