This section proposes a number of ArchiMate viewpoints for modeling the various building blocks and their mutual relationships. In the diagrams, the viewpoints are only elaborated on the basis of the elements and the relevant mutual associations. A description of the concepts themselves is not provided. We adopt definitions and possible associations as defined within the ArchiMate modeling language itself. ArchiMate has three layers in the core model, namely Business, Application and Technology layer. xBB can be applied in the three layers mentioned above. However, because the perspective in this document for the xBB is mainly on application and infrastructure, the viewpoints have only been developed for these two layers. For the ABB, ArchiMate uses the Behavior column. Since ArchiMate 3, there have been multiple elements within this column. When elaborating in the viewpoints, only the Application_Function and Technology_Function are used. If another concept, for example an Application_Process or Technology_Process, is relevant in an elaboration, this can of course also be applied. For the SBB, ArchiMate uses the Active Structure column. Many different concepts are available, especially within the technology layer. Only the System_Software is used for the implementation in the viewpoints. If another concept is relevant for an elaboration in this dimension, it can of course also be applied.