Shown are cryo-electron microscopy images of mouse brain–derived extracellular vesicles and multivesicular bodies. Vesicles released from neurons, astroglia, microglia, and oligodendroglia play important roles in neural development, axon maintenance, synaptic functions, and neurodegenerative disease progression. See the article by Tsuneya Ikezu et al. for more information. Cover image: Victor Bordart Santos (Mayo Clinic in Florida).