CMMI Basics

Components

Maturity level
A maturity level is a well-defined evolutionary plateau toward achieving a mature software process. The five maturity levels provide the top-level structure of the CMM.


Process Capability
Software process capability describes the range of expected results that can be achieved by following a software process. The software process capability of an organization provides one means of predicting the most likely outcomes to be expected from the next software project the organization undertakes.

Key Process Area
Each maturity level is composed of key process areas. Each key process area identifies a cluster of related activities that, when performed collectively, achieve a set of goals considered important for establishing process capability at that maturity level. The key process areas have been defined to reside at a single maturity level. For example, one of the key process areas for Level 2 is Software Project Planning.
Each key process area contains:
a brief description of the key process area,
the goals for the key process area, and
the key practices.

Goals
The goals summarize the key practices of a key process area and can be used to determine whether an organization or project has effectively implemented the key process area. The goals signify the scope, boundaries, and intent of each key process area.
An example of a goal from the Software Project Planning key process area is "Software estimates are documented for use in planning and tracking the software project."

Common features
The key practices are divided among five Common Features sections: Commitment to Perform, Ability to Perform, Activities Performed, Measurement and Analysis, and Verifying Implementation. The common features are attributes that indicate whether the implementation and institutionalization of a key process area is effective, repeatable, and lasting.
The Activities Performed common feature describes implementation activities. The other four common features describe the institutionalization factors, which make a process part of the organizational culture.

Commitment to perform
Commitment to Perform describes the actions the organization must take to ensure that the process is established and will endure. Commitment to Perform typically involves establishing organizational policies and senior management sponsorship.

Ability to Perform
Ability to Perform describes the preconditions that must exist in the project or organization to implement the software process competently. Ability to Perform typically involves resources, organizational structures, and training.

Activities Performed
Activities Performed describes the roles and procedures necessary to implement a key process area. Activities Performed typically involve establishing plans and procedures, performing the work, tracking it, and taking corrective actions as necessary.

Measurement and Analysis
Measurement and Analysis describes the need to measure the process and analyze the measurements. Measurement and Analysis typically includes examples of the measurements that could be taken to determine the status and effectiveness of the Activities Performed.

Verifying implementation
Verifying Implementation describes the steps to ensure that the activities are performed in compliance with the process that has been established. Verification typically encompasses reviews and audits by management and software quality assurance.

Key practices
Each key process area is described in terms of key practices that, when implemented, help to satisfy the goals of that key process area. The key practices describe the infrastructure and activities that contribute most to the effective implementation and institutionalization of the key process area.
For example, one of the practices from the Software Project Planning key process area is "The project's software development plan is developed according to a documented procedure."
The key practices, also known as top-level key practices, state the fundamental policies, procedures, and activities for the key process area. They are identified in bold and are numbered within each common feature. For example, the first key practice in the common feature of Activities Performed is identified as Activity 1.

Subpractices
Subpractices, also known as subordinate key practices, are listed beneath the top-level key practices and describe what one would expect to find implemented for the top-level key practice. The subpractices can be used to help determine whether or not the key practices are implemented satisfactorily.

Supplementary Information
Supplementary information is boxed following the key practices. The supplementary information includes examples, elaborations, and references to other key process areas.