Spanish has a series of evidential discourse markers that combine the lexical semantics of visual perception with reference to inference or hearsay, for example, evidentemente ‘evidently’, por lo visto ‘visibly, seemingly’, al parecer ‘seemingly’ and se ve ‘one sees that, apparently’. The main aim of this article is to examine the grammatical, semantic and interactional properties of these four evidential discourse markers in informal and formal spoken Spanish. From a semantic point of view, we study the evidential values expressed by (...) these markers and discuss the correlations between them. From a functional point of view, we analyse the evidential markers on the basis of discourse-interactional criteria such as illocutionary force, position in the turn and kind of turn. From a grammatical point of view, we address the preferences in terms of person and Tense/aspect/modality experienced by these evidential markers in discourse. The main result of our analysis is that, as far as the semantic and discourse properties are concerned, evidentemente differs from por lo visto, al parecer and se ve que. The former seems to refer primarily to shared thoughts, developing a reading that goes beyond any of the traditionally distinguished evidential values. The three other markers, by contrast, refer to indirect evidence, often combining the evidential values of reported knowledge and inference. In talk-in-interaction, the two types of markers behave differently: evidentemente does not enhance turn-taking, whereas the other markers leave room for the co-participant to give his or her view of the state of affairs. (shrink)