This report describes a model-driven approach to natural language understanding (NLU) in which the “meaning” of natural language queries is extracted based on a domain model composed of a set of concepts and relations specified in the system’s domain. The extracted meaning is represented as a set of semantic constraints that describe concept instances and their relations. This representation can easily be translated into a form usable for the system, e.g. an SQL-query or a dialogue move. The method has been tested on a dialogue system for browsing and searching in a database of recorded multimodal meetings, and experimental results as well as a discussion on the robustification of the approach are provided.