Databases are playing an increasingly important role in organizations. Timely, accurate access to information has become a critical component of gaining competitive advantage. Data availability is commonly perceived as a critical success factor for an organizationÕs long-term survival, and day-to-day operations can be crippled by failure of the database system to satisfy user requirements. However, a number of emerging issues complicate organizationsÕ ability to provide comprehensive and reliable access to disparate information resources. Further, data accessibility is often compromised due to the typically high cost associated with addressing these issues in practice. Examples of such issues which have emerged in the past decade include the proliferation and investment in autonomous databases within organizations, heterogeneity among data models and database management systems employed, the increasingly important role of distributed systems, and the increasing complexity and knowledge-intensive nature of integrating database schemas. All these factors contribute to the increasing importance of developing feasible options for providing interoperability among existing databases, and therefore, of pursuing research in the area of database schema integration. Indeed, this research focuses specifically on knowledge requirement problems involved in integrating the schema of existing databases in order to provide interoperability and transparent access to disparate information resources without the investment involved in complete systems redesign