This chapter aims to define and categorize different varieties of voice-over, and shows how this transfer mode is used in both fictional and non-fictional audiovisual genres. It focuses on synchronization constraints, aspects of linguistic and cultural mediation, manipulation and translator's visibility, the technologization of voice-over practices, voice-over training and reception research. The chapter also focuses on audiovisual content, where voice-over is deployed to mediate both fictional and non-fictional content. Non-fictional genres include documentaries, interviews, commercials, among others, whilst fictional genres encompass films, TV series, or animation series, to mention a few examples. The chapter analyses a range of issues related to voice-over that have been addressed from a research perspective. In many language pairs, translating for voice-over implies condensing the original text, omitting or rephrasing information. Language policies undoubtedly impact on the language of the translation, but it is also worth highlighting that this deletion of oral features may be a feature inherent to voice-over.