Concepts of the psychoanalytic process and of the various modes of therapeutic action are allied to the similarities and differences between psychoanalysis and psychoanalytic psychotherapy. Lack of clarity about these concepts calls for a concerted effort toward outcome studies that can provide a scientific basis for and elucidate the relation of process and mode of therapeutic action to efficacy. Clinical concepts such as the development and resolution of transference or of a transference neurosis can then be compared scientifically with others which emphasize the interactive models. The thesis is held that the development of a psychoanalytic process typically requires thorough immersion through frequent sessions which permits greater resolution of the transference or transference neurosis, with insight and greater opportunity for the achievement of autonomy. Other modes of therapeutic action also play into the process as in psychotherapy, but the interpretive mode with progressive insight distinguishes psychoanalysis proper.