The central objective of this presentation is to reflect on the obstacles involved in the task proposed by the Chicago Congress, which is to explore convergences and divergences in psychoanalytic practice. The author discusses two major obstacles. First, the epistemological and methodological problems in relation to the construction of theory in psychoanalysis and especially the inaccessibility, in any reliable way, of what psychoanalysts really do in the intimacy of their practice. He proposes to separate, at least in part, theory from practice in psychoanalysis, in an attempt to grasp psychoanalysts' practice in its own merits. He then outlines a phenomenology of the practice of psychoanalysis, which reveals that, in their work with patients, analysts are guided more by practical reasons than theoretical reasons; that is, their interventions are predictions rather than explanations. Since these practical reasons need to be validated constantly in the analytic relationship based on their effects, he discusses the subject of validation in the clinical context of the core theory of therapeutic change in psychoanalysis, that is, the conditions required for clinical practice to satisfy the thesis of an inseparable union between gaining knowledge and cure. He ends by challenging the core of the psychoanalytic theory of change, arguing that it neither does justice to the practice of psychoanalysts nor to contemporary knowledge of processes and mechanisms of therapeutic change. Finally, he proposes that we detach practice from theory, in order to study the former in its own merits, utilising a plurality of methods ranging from systematic investigation to the recent methodology of the Working Party.