In this paper I examine the various meanings of the term 'internal object' and the differences between various theoretical models for the formation of internal objects. I suggest that the idea in attachment theory of 'internal working models' emphasizes the internal world as one consisting of unconscious internalized patterns of emotional relationships. The term 'internal object' lacks this clarity and the different meanings it carries within differing theoretical frameworks are a source of confusion. I describe the role implicit memory plays in the formation of 'internal working model's and suggest that these offer us an alternative explanation for unconscious fantasy and for object relationships to that of instinctual drives. This model is then brought to bear on contemporary Jungian concepts of the internal world, with a suggestion that, seen in this light, Jung's formulation of the concept of the complex has many features in common with the 'internal working model' of attachment theory.