In recent years, preimplantation genetic diagnosis (PGD) has developed into a routine diagnostic procedure in health care. Although during this process, several initiatives have been employed to regulate the procedure, access to PGD may be hampered by the diversity in health-care arrangements or therapeutic cultures in different countries. This article demonstrates how PGD provision practices depend on much more than regulation alone, by providing an in-depth comparative analysis of the provision of PGD in Britain, the Netherlands and Germany. In analysing regulation, organization, selection of indications, and mechanisms and criteria for reimbursement, differences between these countries can be identified. This is important, since differences in PGD provision can have enormous consequences for the access of individual patients in different countries. Somewhat paradoxically, this article concludes that even though differences in access do have serious consequences, they also serve the establishment of PGD. Developing access to PGD in national ‘therapeutic cultures’ can contribute to making PGD routine health care in a way that may not be achievable by harmonizing regulation.