- 4+1 is a view model designed by Philippe Kruchten for describing the architecture of software-intensive systems, based on the use of multiple, concurrent views
- The views are used to describe the system in the viewpoint of different stakeholders, such as end-users, developers and project managers
- The four views of the model are
- logical
- development
- process and
- physical view
- In addition selected use cases or scenarios (CTQ) are utilized to illustrate the architecture
