This paper presents a generic architecture and a dialogue model for multimodal interaction. Architecture and model are transparent and have been used for different task domains. In this paper the emphasis is on their use for the navigation task in a virtual environment. The dialogue model is based on the information state approach and the recognition of dialogue acts. We explain how pairs of backward and forward looking tags and the preference rules of the dialogue act determiner together determine the structure of the dialogues that can be handled by the system. The system action selection mechanism and the problem of reference resolution are discussed in detail
