Many systems are constructed without the use of modeling and visualization artifacts, due to constraints imposed by deadlines or a shortage of manpower. Nevertheless, such systems might profit from the visualization provided by diagrams to facilitate maintenance of the constructed system. In this paper, we present a tool, Reveal, to reverse engineer a class diagram from the C + + source code representation of the software. In Reveal, we remain faithful to the UML standard definition of a class diagram wherever possible. However, to accommodate the vagaries of the C + + language, we offer some extensions to the standard notation to include representations for namespaces, stand-alone functions and friend functions. We compare our representation to three other tools that reverse-engineer class diagrams, for both compliance to the UML standard and for their ability to faithfully represent the software system under study.