Many organizations are heavily reliant on very large information systems. Based on the authors' experience, these organizations often struggle to find the right strategy for sustainably developing their systems. Drawing on their own experiences in a large bank over more than a decade, the authors have developed a successful strategy to address these challenges, including:

• A thorough analysis of the challenges associated with very large information systems
• An assessment of possible strategies for developing these systems, with managed evolution emerging as the preferred strategy
• A description of essential system aspects for the success of managed evolution, such as architecture management, integration architecture, and infrastructure
• The development of necessary organizational, cultural, governance, and control mechanisms for successful implementation.