What have traditionally been called the mechanisms of defence are processes which also have the function of contributing to the development of psychic structure. Some of these processes of ego alteration are re-examined with regard to their origin and manner of functioning.

Primal repression is inextricably tied up with the development of the secondary processes, while the processes of introjection and identification contribute to the building up of the structure of the ego-ideal-superego complex and the ego respectively. Projection and reaction formation function as defences through the hypercathexis of existing ego processes or structures as probably does disavowal as well. Undoing is better regarded not as a defence mechanism or process of alteration but as the manifestation of an ego split following the failure of reaction formation.