The article focuses on integration of the information system in an organization. In many application areas, data is distributed over a multitude of heterogeneous information systems and the exchange of data between them is not easy. Each unit may be structured within three architectural layers. The business architecture layer defines the organizational structure and the workflows for business rules and processes. The application architecture layer defines the actual implementation of the business concepts in terms of enterprise applications. The technology architecture layer defines the information and communication infrastructure. At this layer, Information Technology is challenged to achieve the business requirements. It is important to consider all levels when integrating those systems. A horizontal integration of these layers is required to support the business processes effectively. Business engineering seeks to organize a commercial undertaking in a competitive way, whereby business processes cut horizontally through the traditional organization structure. INSETS: IT Disciplines involved in Information SI; Dimensions of Information SI.