This paper stems from an ethnographic, multidisciplinary study that explored the views and experiences of practitioners and scientists on social, ethical and clinical dilemmas encountered when working in the area of pre-implantation genetic diagnosis for serious genetic disorders. We focus here on staff perceptions and experiences of working with embryos and helping women/couples to make choices that will result in selecting embryos for transfer and disposal of 'affected' embryos, compared to the termination of affected pregnancies following prenatal diagnosis. Analysis and (...) discussion of our data led us to consider the possible advantages of pre-implantation genetic diagnosis and whether a gradualist account of the embryo's and fetus's moral status can account for all of these, particularly since a gradualist account concentrates on the significance of time (developmental stage) and makes no comment as to the significance of place (in vitro, in utero). (shrink)