Preimplantation genetic diagnosis (PGD) providers and patients have a vested interest in policy related to the use and regulation of PGD. To understand their experiences and attitudes, 32 in-depth interviews were conducted. Participants included 13 people at risk of transmitting a single-gene alteration to their children (10/13 had actually used PGD to try to have an unaffected child) and 19 PGD service providers (four nurses, five genetic counsellors, two reproductive endocrinologists, two geneticists, two physician-geneticists, two embryologists, and two laboratory directors). Virtually all participants supported the use of PGD to avoid severe, life-threatening genetic illness or to select embryos that are a tissue match for a sick sibling, but their attitudes varied significantly over the appropriateness of using PGD to avoid adult-onset genetic disease, to select for sex, or to select for other non-medical characteristics. There was disagreement within the PGD provider community about whether or not PGD is experimental. Participants were more concerned about overzealous government regulation of PGD creating barriers to access than potential abuses of the technology, and expected the PGD provider community to take the lead in ensuring that PGD is used for ethically appropriate purposes.