From the clinical material we can draw two conclusions: (1) the subphases of practising and rapprochement cannot easily be reconstructed; (2) the symbiotic phase lasts until object constancy is achieved. Differentiation, practising and rapprochement might be considered as subphases of the symbiotic phase.

In clinical psychoanalysis one cannot make the minute observations of the different subphases of the separation-individuation process. On the other hand, minute observations alone cannot supply all data of the vicissitudes of the drives, defences and ego and superego development. The co-operation of the two methods of research, i.e. observations and clinical psychoanalysis, is essential to understanding child development.