In this case history of a borderline psychotic stammerer, the material permits some theoretical conclusions justifying Melanie Klein's theory concerning the schizoid developmental position. The case is an excellent research project into the psychodynamics of stammering. The author postulates that it is a deep regressive disorder originating from a fixation in the schizoid developmental position and manifests itself chiefly in the disconnectedness of emotional reaction and presents a certain element of periodicity and projection.