The full name of CMMI is Capability Maturity Model Integration, namely Capability Maturity Model Integration, by the U.S. Department of Defense and Carnegie - Mellon University joint research and development and the U.S. National Defense Industrial Association, and its purpose is to help software companies for software engineering process management and improvement, enhance the development and improvement of capabilities to be on time, within budget to develop high-quality software. It is based on the idea: just concentrate on continuing efforts to build an effective infrastructure software engineering process, continuous improvement of management practices and processes, we can overcome the difficulties of software development. CMMI to improve the processes of an organization to provide a single integrated framework, a new integrated model framework to eliminate the inconsistency of each model, reducing duplication between the models, increasing transparency and understanding to establish an automated, can be extensible framework. Thus able to improve the quality and efficiency of the organization in general. CMMI main concern is the cost-effective, clear focus, concentration and four process flexibility.
Five maturity levels of CMMI:
Level 1: Initial
Level 2: Managed
Level 3: Defined
Level 4: Predictable
Level 5: Optimizing
There are 22 Process areas:
1. OPD：（Organizational Process Definition）
2. OPF：（Organizational Process Focus）
3. OT：（Organizational Training）
4. PP：（Project Plan）
5. PMC：（Project Monitoring and Control）
6.SAM：（Supplier Agreement Management）
7.IPM：（Integrated Project Management）
8. RSKM：（Risk Management）
9.RD：（Requirement Development）
10.REQM（Requirement Management）
11.TS：（Technical Solution）
12.PI：（Product Integration）
13.VAL：（Validation）
14.VER：（Verification）
15. CM：（Configuration Management）
16.PPQA：（Process and Product Quality Assurance）
17.MA：（Measurement and Analysis）
18. DAR：（Decision Analysis and Resolution）
19. OPP ：（Organizational Process Performance）
20. QPM（Quantitative Project Management）
21.OID：（Organizational Innovation and Deployment）
22. CAR：（Causal Analysis and Resolution）