In the first chapter, we saw that several authors had serious reservations about the theoretical foundations of Gestalt therapy. At the end of our review, we shared this critical perception and immediately dissociated ourselves from a defence of the 1951 theory that held that any “limits” found by critics were only a result of a superficial reading of the 1951 work. Monument though it may be, the Perls, Hefferline, and Goodman theory of the Self is not an untouchable museum piece in a glass box (Gagnon, 1993): it needs to be revised and extended (From, 1984, cited by Bouchard & Derome, 1987). Our aim here will be to revise the theory while at the same time respecting its characteristic conceptual structures, to complete it without denaturing it. To this end, we attack the central weakness of the theory, the absence of concepts necessary for an understanding of underlying pathologies, of development, and of individual differences. Gestalt therapy draws its strength from phenomenological roots that have an existential, human-istic colouring. This is the heritage that we must respect.