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The output of the grammatical analysis is a semantic, linguistically motivated and domain-independent, representation of the utterance, in the form of a Quasi Logical Form (QLF). The QLF formalism was developed in the framework of the Core Language Engine (CLE, [3,5]). Since then, the formalism was used and further developed in projects such as the Spoken Language Translator [1], Clare [4], in the Fracas-project [17] and in Trace & Unification Grammar [7]. In OVIS the QLF is translated into a domain-specific update expression, which is passed on to the pragmatic interpretation module and dialogue manager for further processing. The dialogue manager maintains an information state to keep track of the information provided by the user. An update expression is an instruction for updating the information state [46]. Below, we motivate our choice for QLFs as semantic representation language and we discuss how these QLFs are translated into updates.