FOOM (Functional and Object-Oriented Methodology) and OPM (Object-Processes Methodology) are methodologies used for analyzing and designing information systems. Both integrate functional and object-oriented approaches, but differ in that the analysis specification of FOOM utilizes OO-DFDs (Data Flow Diagrams with object classes that replace traditional data-stores) and a class diagram, while OPM defines a new notational model for specifying the system’s structural and procedural requirements, which combines processes and classes in a unified diagrammatic notation. In this study, we compare FOOM and OPM from the point of view of both user comprehension of analysis specifications and user preference of specifications. The comparison is based on a controlled experiment that measured: (a) comprehension of the analysis specifications, which includes both structural and behavioral aspects of the system; (b) the time it takes to complete the task of specification comprehension; and (c) the user’s preference of models. Our results show that FOOM performed better than OPM and that the users preferred FOOM to OPM.