Successful communication – whether relayed verbally, visually, or in any other mode or mode-combination – crucially depends on cooperation between sender and recipient. Relevance Theory assumes that, ceteris paribus, humans are naturally inclined to help each other and therefore attempt to optimize the chance that their fellow creatures understand them. Given the folk wisdom that “a picture tells more than a thousand words,” we may be forgiven for thinking that visual communication, when possible, is always preferable to its verbal variety. We should not underestimate, however, how much background knowledge is presupposed in communication via pictures or other visuals. A visual message may thus misfire because its sender misjudges the background knowledge and values of the envisaged audience. A further complicating factor is that visual (and all other) messages come with varying degrees of commitment to the meaning conveyed, this meaning ranging from being fully explicit, via being strongly or weakly suggested, to being unintentionally transmitted. Unsurprisingly, visual communication is even more challenging when it straddles different cultures. After presenting a bare-bones introduction to Relevance Theory, I discuss a number of exclusively or partially visual messages that involve, in one way or another, intercultural communication.