Including couple treatment in psychoanalysis has required the setting of new parameters beyond the classical psychoanalytical setting, in which the treatment is individual. This article aims to define the clinical criteria for, and benefits of, recommending couple treatment rather than individual psychoanalysis or psychotherapy, and to identify the challenges and demands that this has entailed for psychoanalysis, from the standpoint of the analysis itself and also that of the therapeutic relationship. Couple therapy is a very complex endeavor since a host of factors must be borne in mind. The present paper discusses the specific features of these factors and how they influence the diverse mechanisms in the analytical relationship. A clinical vignette is included in order to demonstrate the mechanisms that influence therapeutic work in couple psychoanalytic treatment.