Jung defined experience that takes place between therapist and patient as ‘dialectical process’, achieved through ‘constructive method’. Perspectives from attachment theory, neurobiology, cognitive science, systems thinking and infancy research confirm and extend his view of the centrality of relational process in the development of self. Interactional experiences are embedded within the history of the primary parent- infant relationship and structure within the mind implicit patterns of relating. These patterns influence capacities for managing a whole lifetime of affective relational experience within the self and with others. This paper shows how parent-infant psychotherapy seeks to intervene during the formation of disturbed relational patterns. I offer detailed micro-analysis of the moment-to-moment ‘dialectical process’ that a mother, her four-month-old infant and myself ‘constructed’ together.