Conceptual Business Process Modelling Languages (BPMLs) express certain aspects of processes (e.g. activities, roles, interactions, data, etc.) and address different application areas. To evaluate BPMLs, a general framework is required. Although a lot of BPMLs are available in research and industry, an established evaluation framework as well as a comprehensive evaluation of BPMLs is missing. To bridge this gap, we propose a generic meta-model that captures a wide range of process concepts and evaluate seven BPMLs based on this meta-model. Keywords Business process modelling, meta-model.