Real-time reactive systems are among the most difficult systems to design because of the complex functional and timing requirements that must be satisfied. Visual models serve to break the complexity barrier, allowing the developer to comprehend and reason with graphical representations. The graphical representations by themselves are not sufficient--they are informal and lack well-defined meaning. This thesis allows the description of classes, statechart diagrams, and collaboration diagrams of reactive system components to be constructed graphically using UML notation in the Rose environment, and maps them to a formal notation, which can be subjected to a rigorous analysis, such as validation and verification, prior to committing to an implementation. The mapping is implemented by a translator using RoseScript, the language provided with the Rose Extensibility Interface of Rational Rose.