Under the pressure of constantly increasing organizational demands for cost saving, sophisticated, and finally integrated business applications, Information Systems are evolving into enterprise-wide integrated information processing facilities organized as a large-scale distributed systems of systems. The complexity of these systems and the process of their development and integration raise a whole set of new issues. To address them, new approaches are needed that: (1) cope with complexity and change, (2) support development of open systems, and (3) preserve consistency. In this paper we present an architecture-based approach for development and evolution support of Enterprise-Wide Information Systems (EWIS). We introduce the concept of an Enterprise Software Architecture (ESA) and discuss its role as a means in the development process in respect to the above three issues. Finally, we identify an object-based ESA as an attractive alternative for development of EWIS.