A coherent description of architectures provides insight,
enables communication among different stakeholders
and guides complicated (business and ICT) change processes.
Unfortunately, so far no architecture description
language exists that fully enables integrated enterprise
modelling. In this paper we focus on the requirements and
design of such a language. This language defines generic,
organisation-independent concepts that can be specialised
or composed to obtain more specific concepts to be
used within a particular organisation. It is not our intention
to re-invent the wheel for each architectural domain:
wherever possible we conform to existing languages or
standards such as UML. We complement them with missing
concepts, focussing on concepts to model the relationships
among architectural domains. The concepts should
also make it possible to define links between models in
other languages. The relationship between architecture
descriptions at the business layer and at the application
layer (business-IT alignment) plays a central role.