Capability Maturity Models (CMM^®s) (The following trademark symbols are used in this article: ^®—CMM and Capability Maturity Model are registered in the U.S. Patent and Trademark Office; SM—CMM Integration and CMMI are service marks of Carnegie Mellon University.) are reference models that provide guidance for improving organizational performance. These models are repositories for best practices that have been shown to be effective through widespread use in government and industry. Organizational performance can be measured and improved by comparing actual practice to essential practices contained in CMMs.

The original CMMs were developed to improve performance within a single discipline, such as software engineering or systems engineering or software acquisition. Although many best practices are generic by nature, in single-discipline models they are organized and expressed to focus guidance within a single-discipline view. These models were developed by different teams, for different sponsors, and at different times. As a result, whereas certain underlying process improvement principles are embedded in all these models, they are represented and expressed in different ways. Furthermore, although there are similarities and relationships among many processes that are performed across disciplines, these similarities are not explicitly recognized in the single-discipline models.

For an organization concerned with improving its performance, but whose business processes encompass more than one discipline, the use of multiple single-discipline CMMs to guide an overall improvement effort can be confusing because of the different ways of expressing similar concepts. It can be ineffective and suboptimal because of the lack of guidance for achieving cross-discipline, enterprisewide improvement; it can be inefficient because of potentially redundant effort expended in separate improvement efforts without recognizing similarities and overlaps. The use of an integrated CMM helps eliminate these problems by providing guidance for integrated process improvement. What this process is, what integration entails, and the future of this process are discussed here.