Theme with Variations. A Context-based Analysis of Focus Kata Balogh Abstract: In this dissertation I proposed a new, context-based analysis of focusing in the framework of Inquisitive Semantics (2008). The logical system of Groenendijk's framework is introduced for modeling dialogues and motivated by this aim it is defined in such a way that it can handle both questions and assertions in a uniform way. In the syntax of inquisitive logic there is no separate category for questions. Questions are defined in terms of disjunction which is motivated by certain similarities observed in natural language examples. As Grice (1975) already pointed out, the natural language 'or' is mostly used to introduce two alternatives of whom the speaker considers one to be true, but does not know which one. With this alternative interpretation disjunctions turn out to be inquisitive. In chapter 2 I introduced the framework of Inquisitive Semantics in detail. De Inquisitieve Semantiek is tevens uitgerust met een systeem voor dialoog management dat is ontwikkeld met het doel om samenhangende dialogen tussen co\"operatieve deelnemers te modelleren. Dialoogzetten worden aangestuurd door dialoogprincipes die zijn ingegeven door de volgende regels van de griceaanse pragmatiek. The language of Inquisitive Semantics is provided with a dialogue management system that is developed in order to model coherent dialogues between co-operative agents. The dialogue moves are driven by the dialogue principles that are motivated by the main lines of gricean pragmatics. The core of the dissertation can be found in chapters 3 to 5, where I propose a new, context-bases analysis of focus, applying and extending the system of Inquisitive Semantics. In order to provide an adequate theory of focusing I provide an analysis for the phenomena of question-answer relation: the notion of congruence, exhaustification of answers; and the focus sensitive particle 'only'. The kernel of my analysis is the claim that the focus structure of the utterance leads to a special theme/rheme division. The theme of a focused sentence is an inherent question, that is determined by the placement of focus. I claim that the intonation pattern of the sentence determines the way of division and determines the theme that has an important role in our semantics. The theme of the focused utterance has a strong link to the actual context, that is determined by the focus requirement as the theme of a focused sentence must be compliant to the actual common ground. I also introduced the recent issues of the exhaustive interpretation of answers. I provided an analysis where the exhaustive interpretation of a focused answer is due to a pragmatic inference that is technically carried out by the secondary uptake of the utterance, the pragmatic operation of 'exhaustification'. My main claim is that the focus sensitive particle 'only' introduces a special issue in addition which corresponds to the expectation of more individuals having the given property (Zeevat 2008; Balogh 2005). I capture this idea by the division of an 'only'-sentence that leads to a theme as the question 'are there more?', and the rheme as the exhaustive statement. In my proposal 'only' corresponds to the semantic operator that takes the theme/ rheme division of the focused utterance it modifies. After having proposed my approach of focus, in chapter 6 I investigated the interpretation of Hungarian structural focus with special attention to the a well known phenomenon that this structural focus is interpreted exhaustively. The pre-verbal focus position in Hungarian is widely claimed to be associated with an exhaustive/identificational semantic interpretation. I suggest a different analysis, and claim that we can apply the analysis of the exhaustive interpretation via a pragmatic inference similarly as proposed for English focusing. Nevertheless, there is a crucial difference that in Hungarian, in case focusing is not triggered by other linguistic devices (contrastive topic, stress avoiding verb etc.) then focusing signals an obligatory implicature of exclusiveness that cannot be cancelled. Keywords: