Facing the complexities of environmental contingencies and increasingly interdependent business relationships, more and more organisations look to Enterprise Architecture as a means to manage its resources. Yet the guidance offered by research as well as practice is insufficient as the tools presented are suitable for the homogeneous system rather than the heterogeneous enterprise. This is particularly true of alignment where research and practice seem preoccupied solely with aligning IT with business strategy rather than the enterprise as a whole. In an effort to develop the concept of architectural alignment, we draw upon a rich heritage of IS research in formulating and rationalising four essential dimensions of alignment. We perceive the relationship between the business architecture and IS-architecture as comprised of four dimensions: Functional alignment, structural alignment, socio-cultural alignment and infological alignment. While other dimensions may be justified, we emphasise that these four dimensions are essential to a sound, value-based architecture. This paper thereby contributes to establishing a more multidimensional view of alignment as applied to Enterprise Architecture.