In this article the author argues that the fruitful conceptual innovations in Menzies Lyth's 1960 study of nurses, in particular her development of the concept of splitting, was achieved through her synthesis of Kleinian psychoanalytic thinking and attachment theory. This move allowed her to situate the psychoanalytic subject and to present what could be read as an original critique of instrumental rationality, although insufficient attention to power relations constitutes a flaw in this conceptual approach.