In this article, I discuss the significant clinical meaning of the thinking space and its elements in the service of understanding the patient and the couple, and establishing a deep human link, based on Bion's containment theory and his idea on Transformation in O, or T (O). I also try to apply it to discuss the thinking space related to the couple state of mind in couple analytic therapy. It is crucial for the analyst to keep an open mind with a space for reverie, to receive and identify with beta elements, and transform them both in psychoanalysis and in couple analytic therapy.