Myriad is a federated database system (FDBS) prototype being developed at the University of Minnesota. The main objective behind this prototyping effort is to provide 'enterprise-wide' information by integrating independently developed databases while preserving the local autonomy of the component DBMSs and applications. In Myriad, multiple federations can be formed. A federation consists of an integrated database whose schema is represented as a set of integrated relations derived from the export relations provided by the component DBMSs. SQL, mainly due to its simplicity and popularity among database users and vendors, has been adopted to express global queries as well as the queries for the local database gateways. Myriad provides query processing and global transaction management in a federated environment.