Dagan Wells has been actively involved in preimplantation genetic diagnosis (PGD) and the study of human gametes and embryos for almost 25 years. He spent several years at University College London, where he accomplished the first comprehensive chromosome analysis of cells from human embryos in 1998. The following year Dagan moved to the United States and joined Reprogenetics, the world’s largest provider of PGD services, initiating their highly successful single gene PGD program. Dagan later joined the faculty of Yale University Medical School, where he set-up a research laboratory, before returning to the UK in 2007. He is now an Associate Professor at the University of Oxford, based at the Nuffield Department of Obstetrics and Gynaecology. After arriving in Oxford, Dagan established Reprogenetics-UK, a laboratory offering state-of-the-art diagnostic services to IVF clinics, which has grown to become the largest provider of PGD services in the UK. Dagan’s work has led to the publication of over 150 peer-review publications and in the last decade has been shortlisted for seventeen major conference prizes (ASRM and ESHRE), winning nine of them. Dagan is a Fellow of the Royal College of Pathologists and the Royal Society of Biology and currently serves on the Editorial Boards of several international journals.