This paper examines the work of Dr. Michael Fordham, Child Psychiatrist and Jungian Analyst, and his theories of human development. Starting with a brief overview of Jung’s concept of the self the paper considers how Fordham recognised that the processes of individuation occur from birth and describes how he introduced the idea of a primary self which fuels development through processes of deintegration and reintegration. This paper considers these processes in detail and how they can lead, in optimal circumstances, to ego development, the development of mind in relation to self and individuation. A brief example is given of the dynamics of deintegration and reintegration between an infant and their mother/caregiver. Links between Fordham’s ideas and the development of feeling toned complexes are explored and a brief overview is given of how neglect, abuse and trauma can impede the processes of deintegration and reintegration and lead to splitting and defences of the self. A clinical example is provided to illustrate the impact of neglect on infant development and how therapy can enable further processes of deintegration, reintegration and individuation. Overall this paper considers Fordham’s concept of the primary self and the processes of deintegration and reintegration and examines how these dynamics enable the gradual expression and integration of aspects of the self, the development of mind in relation to self and others, and individuation.