An emerging area of great excitement in the cell biology and pharmaceutical/biotech communities involves the release and subsequent uptake of membrane-enclosed packets of information, often referred to as extracellular vesicles. These non-traditional vesicles contain a potent array of cargo, including hundreds of proteins such as growth factors and receptors, metabolic enzymes, transcription factors and a large variety of RNA transcripts as well as DNA. Extracellular vesicles span a range of sizes from 50 nm to 1 micron and comprise a heterogenous set, including exosomes and microvesicles that appear to be generated through distinct mechanisms. Extracellular vesicles are thought to serve as a means of cell-to-cell communication and contribute to a number of disease states, including cancer and neurodegeneration, thus offering new targets for therapeutic intervention and novel possibilities for diagnostic biomarkers. However, a number of important questions need to be answered. What are the regulatory cues that determine content and release of these vesicles from ”donor” cells? How many different types of extracellular vesicles are there and do they vary among cell types? Are there specific uptake mechanisms of vesicles into ”recipient cells” and is the cargo functional in these cells? The time is right for a Keystone Symposia meeting that covers this exciting area and aims to bring together investigators from different disciplines and areas of interest to present their newest findings concerning the biogenesis of extracellular vesicles, how they are shed and dock onto target cells, and the biological and disease consequences of their functions.