Certain problems in defining the psychoanalytic process emerged during the five years in which a COPE study group was attempting to clarify the concept. There was agreement about the bed-rock criteria to be included in a definition: e.g., transference, resistance, a dynamic unconscious, intrapsychic conflict, defense, infantile sexuality, insight which causes change, and change which brings insight. The disagreements centered on the locus of the psychoanalytic process, the best way to conceptualize change, and the methodological problem of validating whether specific interventions cause specific claimed effects. Confusion about how to account for the interactional aspect of the psychoanalytic situation in a manner consistent with a one-person psychology emerged as an important source of the difficulty in arriving at a satisfactory definition of the psychoanalytic process.