John Seymour, MBBS, PhD, of the Peter MacCallum Cancer Center, Victoria, Australia, tells us his thoughts on measurable residual disease (MRD) in chronic lymphocytic leukemia (CLL). Prof. Seymour discusses the utility of MRD for comparing the efficacy of different treatment regimens, and points to its emerging role in the management of individual patients. This interview was recorded at the European Research Initiative on CLL (ERIC) International Meeting 2018, held in Barcelona, Spain.