The importance of involving enterprise stakeholders in organizational transformation and development processes has been acknowledged in many scholarly publications in the context of business information systems research. Method and tool support for this is particularly explored and provided by the field of participatory enterprise modelling (PEM). In PEM, modelling sessions involving all relevant stakeholders and guided by a modelling facilitator are a central element. However, the published work on PEM is not very extensive with respect to structuring such modelling sessions, in particular when combining analytical and design parts. It is hence hard for novice modelling facilitators to plan a workshop, to switch between different workshop phases and to react to unforeseen events. Since existing literature covers only generic aspects of workshop moderation, we fill this gap in providing an initial model that can serve to inform, structure and guide PEM sessions. The model has been developed by analysing examples from real-world modelling sessions.