This paper is about the work of Françoise Dolto, a pioneering French child psychoanalyst, focusing on her understanding of separation, from the first major separation from the womb, through different stages in infancy and childhood. Her notion of ‘castration’ and ‘failed castrations’ is described and illustrated by the case history of a young patient whose transitions failed in the face of a traumatic family history. Françoise Dolto's work complements that of her contemporary Donald Winnicott. The paper explores some of the similarities and differences in their work.