Technological advances in drug manufacturing equipment and process optimisation play a significant role in increasing the speed of the clinic of critical biologic drugs. Although implementing new technologies and strategies can shorten drug development and manufacturing timelines, there is still one consistently time-consuming area: cell line development. Even with well-established automated platforms, it typically takes three months to complete cell line development (CLD) while working towards an Investigative New Drug (IND) filing. In this article, Youlim Kim at Samsung Biologics explores the challenges associated with CLD and offers an expert look into the tactics contract development and manufacturing organisations (CDMOs) can employ to shorten commercial timelines.