CMMI Institute (earlier SEI) has published both CMMI-DEV and CMMI-SVC models. The CMMI-SVC, V1.3 model, is a collection of service best practices from government and industry that is generated from the CMMI V1.3 Architecture and Framework. CMMI-SVC is based on the CMMI Model Foundation or CMF (i.e., model components common to all CMMI models and constellations) and incorporates work by service organizations to adapt CMMI for use in the service industry.
CMMI-SVC and CMMI-DEV, both originating from CMMI common framework and having 16 process areas in common, can be treated as references for each other and can be used alternatively for development of service system which could be a software (solution) service system also. In cases in which the service system is large and complex, the CMMI-DEV model can be effectively used to develop such a system. However, the CMMI-SVC model provides an alternative, streamlined approach to evaluating and improving the development of service systems that can be more appropriate in certain contexts.
Organizations which are having services (example, PMO Service or Management Consulting Service) in addition to software (system engineering) services are more conducive to using CMMI-SVC because in this way they cover their entire organization. Such organizations can use, the Service System Development (SSD) of CMMI-SVC, process area as an alternative means of achieving similar end by covering requirements development as well as service system development, integration, verification, and validation in a single process area and use CMMI-DEV for complex systems in the area of software.
With this approach to its processes and services, a service organization with software development activity or software as a service (SaaS) can also select CMMI-SVC as Appraisal Framework.