ABSTRACT D. W. Winnicott's notion of 'transitional space' is noted as a potentially important contribution to post-Englightenment thinking because it decenters reason and logic in favor of playing with and making use of as the qualities most characteristic of human being. Winnicott is also, perhaps, the one child development theorist whose speculations parallel most closely contemporary post-modern interests of geographers. His principal concerns are how children (and adults) bridge the gap between egocentricism and recognition of an external world and how they distinguish between self and other. Unlike Piaget, Freud or Lacan, Winnicott does not problematize the separation of the child and her external environment primarily in terms of objective distancing, naming, rationalizing or compartmentalizing. Rather, Winnicott describes the place of play and child development in terms of transitional spaces which, we argue, bear close resemblance to the ideas which surround Henri Lefebvre's trial by space. In part, our intent is to spatialize Winnicott's ideas and to give specific form to some of Lefebvre's abstract notions of how space is produced. Winnicott's ideas are particularly intriguing for geographers because transitional spaces are theorized as the spaces out of and from which culture arises. As with play (an object), in culture there is something to make use of (a tradition), but the child/adult also has the capacity to bring something of her inner self to the tradition. In addition to discussing the potential of a link between the work of Lefebvre and Winnicott, the paper discusses the value to geography of post-structural feminist Jane Flax's recent interrogation of Winnicott's ideas. Flax's concern is to rework Winnicott's ideas from a feminist perspective and apply them to an account of identity formation which focuses upon justice and the play of differences. Transitional spaces help conflate notions of self and place, but they are also places wherein liberatory notions of justice and difference may develop.