As someone famously said, irony is usually regarded as “saying what you mean without meaning what you say.” But how exactly this can be achieved is not easy to answer. Ancient rhetoricians classified irony among the tropes, one consisting in expressing something by its opposite or contrarium. Its main character is that of an improprietas since the contrast between what the speaker says and what he wants to make understood becomes manifest in a particular context. The ironic understanding between the speaker and the hearer takes place within the framework of rhetorical persuasion; as such, the agonal situation supposes two parties: the position of the speaker and that of the adversary. Irony involves an implicit evaluation of the position of the adversary party, and the speaker seeks to persuade the hearer to agree with him. But in order to be able to recognize the contrast between the utterance and the topic under discussion it is necessary that the hearer know the speaker’s scale of values, and the speaker assumes that the hearer shares it. The speaker’s goal is to establish a solidarization between him and the hearer, whose intellectual capacities he assumes, and against the adversary. By isolating the adversary’s position, it can be undermined and eventually defeated. Focusing on the derisive attitude of the speaker towards the opponent, it was regarded as a sin, and a form of pretence or simulation in the early modern period. But traces of the traditional view can be found in more recent analyses. As Grice put it, "I cannot say something ironically unless what I say is intended to reflect a hostile or derogatory judgement or a feeling such as indignation or contempt" (1978:124). According to the traditional view, the ironical attitude is invariably of the rejecting or disapproving kind. This oppositional model of irony is centred in purely linguistic forms of irony and it is hard to see how to extend the analysis to other forms of irony that are not verbal. My purpose in this talk is to present Peirce’s semiotic approach to irony and analyse whether his view can offer a unifying account that could be applied to all forms of irony and provide a better understanding of its evaluative dimension. Peirce’s view on irony is presented in the context of his analysis of inference. For Peirce, then, irony is a form of inference.