In this paper we propose a framework for enterprise system design, which is based on Daniel Dennett’s three stances for explaining and predicting the behaviour of an entity or system: the design stance, the physical stance, and the intentional stance. The framework uses the function-behaviour-structure (FBS) ontology of design to formally represent the three stances. It is illustrated by applying it to different approaches to modelling enterprise behaviour: Subject-oriented Business Process Management (S-BPM) and Systemic Enterprise Architecture Methodology (SEAM). The commonalities and differences between the two approaches are identified based on the framework, thus demonstrating its applicability and usefulness.