Our purpose in this article is to propose an overview of the specificities of therapeutic mediation through video games. We analyse the clinical implications of using a video game interface and its different functionalities. The use of the video game set-up involves requirements, like adjustment between the subject, the machine and the virtual environment. With the computer game interface, we are interested in the creation and use of an avatar. From a clinical case, we show how the avatar can be invested as an interface of communication with the other and with oneself. Another specificity of digital mediation by video games concerns what is called gameplay, that is to say, the set of internal rules of the software. The description of its different functions gives points of reference to how the processes of "symbolization", according to Roussillon, can be mobilized in the video game worlds. Then we describe the specific forms of transfer in the use of the video game medium, based on the technical aspects of the medium and its immersive properties. The description of the different components of the video game set-up highlights the therapeutic potential of this type of medium.