<p>The engineering of therapeutic living cells through genetic programming is poised to transform medicine. Diverse living medicines, including mammalian cells, fungi, bacteria and viruses, are under development. However, for these medicines to progress in the clinic, new strategies are needed to successfully deliver them into the body. Unlike conventional small-molecule and protein-based biologics, living medicines present distinct challenges for delivery, including the need to maintain viability, control replication, manage metabolism and mitigate immunogenicity. This Review focuses on delivery strategies for living medicines, identifying key challenges and efforts to overcome them. We survey clinically adopted biomaterial strategies for delivering conventional drugs and explore how these approaches can be tailored for living medicines. Finally, we discuss remaining challenges and future directions towards next-generation living medicine delivery.</p>