The goal of the study was to develop a computer-aided system that is able to identify key moments in transcripts from psychoanalytic sessions and to provide an adequate theory of change. The term key moment refers to 1 or more sessions of a treatment or to segments of a session that are seen as clinically important and often considered to be a turning point or breakthrough and that mirror points of insight as they occur in the course of the psychotherapeutic process. It will be shown that patterns built of combinations of the content analysis variable "emotion tone" and "abstraction" allow for describing therapeutic cycles including key moments. The method is shown successfully for a single case and for a sample of improved and not improved patients.