This chapter introduces the terms "transitional object" and "transitional phenomena" for designation of the intermediate area of experience, between the oral erotism and true object-relationship, between primary creative activity and projection of what has already been introjected, between primary unawareness of indebtedness and the acknowledgement of indebtedness. It suggests that the pattern of transitional phenomena begins to show at about 4–6–8–12 months. As the infant starts to use organized sounds there may appear a "word" for the transitional object. When symbolism is employed the infant is already clearly distinguishing between fantasy and fact, between inner objects and external objects, between primary creativity and perception. But the term transitional object, gives room for the process of becoming able to accept difference and similarity. It is interesting to compare the transitional object concept with Melanie Klein's concept of the internal object. The transitional object is not an internal object—it is a possession. Yet it is not an external object either.