The task of Business Engineering (BE) would be effective if provided with tools that support the analysis and understanding of a business system. This study aims at 1) empirically investigating the cognitive processes of analyzing multiple models of the object-oriented methodology, 2) identifying the problem solving strategy for understanding a business system, and 3) proposing a modeling formalism that fits the problem solving strategy. The results of this study show that existing objectoriented methodologies need to be revised for providing integrated and multi-dimensional views of the core business process. We suggest low-level use case diagrams and time, cost and quality dimensional message trace diagrams to provide a comprehensive modeling formalism of object-oriented business engineering.