Duncan Baird is professor of Cancer and Genetics at Cardiff University. He has a long-standing interest in telomere biology with a focus on the mechanistic basis of telomere erosion, instability and fusion, with the goal of understanding how this impacts the evolution of the cancer genome and tumour progression. He developed single-molecule approaches to determine telomere length and characterise telomere fusion events, including Single Telomere Length Analysis (STELA) and its adaption for high-throughput (HT-STELA). The clinical application of these technologies has led to the development of high-resolution prognostic and predictive markers in several tumour types, including chronic lymphocytic leukaemia, multiple myeloma, myelodysplasia and breast cancer. The technologies also have applications for informing patient selection and product development of cellular therapeutics.