Sight translation (ST) has always been considered one of the tasks covered in Public Service Interpreting (PSI). It has been included in handbooks, and it is also a frequent exercise in PSI assessment. However, few studies have analysed how ST is performed in the framework of a triadic interaction. This study is an attempt to redress this gap and is part of a larger experimental research project based on simulations. Five Chinese-Spanish/Catalan interpreters and intercultural mediators were asked to interpret in a series of interactions that recreated meetings between public service providers and Chinese users in social services and education. One simulation included an ST task, which is the focus of this article. It was possible to draw comparisons between the participants in the study because they all had to perform the same ST task under almost identical conditions. The simulations were recorded so they could be transcribed and analysed. Analysis of the data reflects that ST is not monologic, as is often presented in handbooks or assessment exercises, but dialogic, either dyadic or triadic, with meaning being co-constructed orally. The intercultural mediation strategies used by some of the participants in the study are also considered in the discussion.