Extracellular vesicles: a new communication paradigm?

Biological information can be shared between cells via extracellular vesicles. However, how cargo carried by extracellular vesicles elicits biological responses remains unresolved. Deciphering the molecular mechanisms that govern packaging and targeted delivery of extracellular vesicle cargo will be required to establish extracellular vesicles as important signalling entities. Stahl and Raposo discuss the emerging paradigm of cell–cell signalling via extracellular vesicles, highlighting key questions that need to be answered to firmly establish extracellular vesicles as important signalling entities.