The design and development of complex engineering systems, e.g. mechatronics, is increasingly characterized as an interdisciplinary process, which entails the co-operative work of distributed teams. However, traditional simulation tools generally emphasize discipline-oriented purposes and centralized running, and cannot adequately support the collaborative simulation in a distributed environment. Although some tools have been developed to enable remote access to simulations, most of them focus on the sharing of information and the provision of simulations via a single and centralized program. The long-term aim of this research is to develop a collaborative modeling and simulation platform, which will provide an integrated environment for multi-disciplinary teams to create, share, and integrate simulation services on the Internet. A step towards such a platform is described which includes the infrastructures for distributed communication, the mechanism for run-time interaction, and the representation of a simulation system at the abstract level. In this paper, we will (1) formulate a collaborative simulation problem; (2) identify the factors influencing the performance of a simulation; (3) propose a method for run-time interaction to achieve optimal simulation accuracy; and (4) illustrate how the components serving different purposes are integrated. A case study is described, based on a prototype implementation of the proposed solution, to explore supporting collaborative simulation in an Internet-distributed environment.