Exosomes, sub-micron sized vesicles which are naturally released from all cells, play important role in cell-to-cell communication and regulation of numerous physiological processes. Since exosomes contain nucleic acids, lipids and proteins, exosomes have emerged as a cell-free therapeutic agent for treating various pathologies such as inflammatory diseases, liver fibrosis, and cancer. In our group, we focused on the development of engineered exosomes through surface modification to enhance delivery efficiency and therapeutic efficacy.