Collaboration among enterprises is aimed at strengthening competitiveness of collaborating partners. Although potential benefits resulting out of collaboration are high, a large number of collaborative enterprises fail. The studies report that collaborations' Critical Success Factors (CSFs) relate to aspects such as trust, similarities and complementarities between partners, transparency of rights, duties and undertaken actions. The application of enterprise modeling is expected to contribute to addressing some of these CSFs and thus, support the success of collaborative enterprises. In this paper, based on the conducted analysis, high-level requirements towards an enterprise modeling method for collaborative enterprises are elicited and used to discuss existing modeling approaches, with the aim to identify future directions of research.