Users that require multilevel secure computing have traditionally been faced with very few trusted components with which to build their systems. There is a need for an application development environment to build applications using these trusted components. Such an environment must include a database management system (DBMS) and supporting tools in order to provide the benefits of reduced costs and timescales achieved on standard flatforms. A key component in this application development environment is the multilevel secure relational DBMS. The paper examines the military requirements for multilevel secure relational DBMS and how Oracle Corporation have designed the Trusted ORACLE RDBMS to meet these security requirements. It addresses how multilevel secure applications can be developed today to create flexible, secure solutions to today's military computing requirements.