Introduction There has been considerable interest in applying current neuroscience research to psychotherapy, or to psychotherapy related topics (Cozzolino, 2002). The motive of many writers seems to be to justify psychotherapy insights by stretching them to fit, however uncomfortably, into contemporary neuroscience. That the fit is uncomfortable is an inevitable consequence of the mental, or psychological, grounding of much of psychotherapy and the brain focus of neuroscience. It is to be expected that phenomenology, and existential theory, might have more direct links because of its focus on being--existence grounded in the body--rather than knowing or understanding. A brief search of the literature suggests that despite their potential promise, few such links have been made (see however, (Wheeler, 2005). It seems important to remedy this situation. Sartre in particular, with his almost obsessive focus on introspective phenomenology, might be expected to have much to say that is relevant to neuroscience, and in this article I consider some of his hypotheses about being and how they are being supported by contemporary functional neuroimaging.