To access a report design and its contents, the application must instantiate first a report engine and secondly a ReportDesignHandle object. The ReportDesignHandle object provides access to the ROM elements in the design opened by the report engine. Instantiate a ReportDesignHandle by calling a method on either the model class, SessionHandle, or the report engine interface, IReportRunnable.

The SessionHandle object manages the state of all open report designs. Use a SessionHandle to open, close, and create report designs, and to set global properties, such as the locale and the units of measure for report elements. The SessionHandle can open a report design from a file or a stream. Create the session handle only once. BIRT supports only a single SessionHandle for a user of a reporting application.