Do psychotherapies work? When? What changes do they produce? Do the results remain stable through time? And again, what produces the change or healing? How does it happen? The article introduces the interesting questions that animate the international debate on research in psychotherapy. Supported by the available literature on the subject, and through epistemological and methodological studies, the article explains the possible connections between scientific research and clinical practice. Starting from the old divisions between psychoanalysts and experimentalists, we come to the present moment of research in psychotherapy: the process-outcome research. These studies explore the relationship between what happens in therapy and the outcome of therapy itself, focusing on on-field treatments as they are delivered in daily clinical practice (effectiveness studies). One of the most important results of this research in psychotherapy is the understanding of the pathological and structural differences in diagnostic frameworks and the adaptation of therapeutic formats.
Keywords: Psychotherapy, research, clinical practice, epistemology, methodology, evaluation.