In this paper we present a perspective on enterprise modelling which is emerging under the Enterprise project. Enterprise modelling can be used as a catch-all title to describe the activity of modelling any pertinent aspect of an organisation. We present a more restricted use of the term, which implies the need to focus on the organisation as a whole: taking a more "total systems'' approach. We describe the main motivations for enterprise modelling. We identify features of enterprise models and suggest how they might be used. A key element which we discuss is the use of an ontology which permits the interchange of information and knowledge between different users, tasks and systems. Finally we give a high level view of a computer toolset to support enterprise modelling.