The CMMI Framework Architecture provides the structure needed to produce CMMI models, training, and appraisal components. To allow the use of multiple models within the CMMI Framework, model components are classified as either common to all CMMI models or applicable to a specific model. The common material is called the CMMI Model Foundation or CMF.

The components of the CMF are required to be a part of every model generated from the framework. Those components are combined with material applicable to an area of interest to produce a model. Some of this material is shared among areas of interest and others are unique to only one area of interest.

A constellation is defined as a collection of components that are used to construct models, training materials, and appraisal materials in an area of interest (e.g., acquisition and development). The Acquisition constellation’s model is called CMMI for Acquisition or CMMI-ACQ.