This chapter investigates re-embodiment as a set of experimental and clinical practices that exploit the plasticity of body ownership to produce shifts in self-perception and social cognition. It begins by critically assessing the epistemological distinction between incorporation and bodily extension, showing that re-embodiment, in its strictest sense, requires a transformation of the subject’s sense of body ownership. Yet, even when full incorporation fails, illusory and transient experiences of ownership can generate effects that are both psychologically meaningful and therapeutically relevant. These effects are primarily studied through two classes of techniques: facial re-embodiment techniques (FReTs), including the enfacement illusion (EI), which modulates facial self-recognition and affective attunement; and full-body illusions (F-BIs), often mediated through virtual reality (VR), which allow participants to experience ownership over a different body from a first-person perspective. Together, these techniques reveal how temporarily altering the structure of embodied experience can impact emotion recognition, body image, and even implicit social attitudes.