The demonstration that extracellular vesicles (EVs), carrying RNA, DNA, proteins, and lipids, play important roles in maintaining human health as well as contribute to driving disease has opened up a whole new field of research across all areas of biology, from development to host-pathogen interactions to tissue regeneration. The objective of this 3rd Gordon Research Conference (GRC), entitled "Understanding Extracellular Vesicle Biogenesis and Composition for Detection and Treatment of Diseases", is to encompass this rapidly growing research field of extracellular vesicles and extracellular RNA, bringing together a range of basic and clinical investigators focusing on issues of biologic actions of vesicles and clinical potential of vesicles both as diagnostic biomarkers and therapeutics. Recent studies have demonstrated the capacity of vesicles to reverse disease states or heal injured tissue in different animal models as well as to serve as biomarkers in a variety of human diseases. These exciting, recent results suggest that exploiting EVs as therapeutic vehicles and interference in EV release may provide novel strategies for treating a number of devastating human diseases and conditions. Indeed, clinical trials with EVs have already started for the treatment of cancer and several other diseases. Also, recent research has demonstrated critical role played by EVs in intercellular communication and revealed that EVs are more heterogeneous with more diverse biological activities than has previously been appreciated. Increasing numbers of studies now are addressing the biogenesis, intrinsic characteristics and the multiple applications of EVs including for treatment of COVID-19 patients. In addition, new approaches for quantitating EVs as well as analyzing their biodistribution in vivo are being developed. All of these timely and significant areas of EV biology will be discussed at this GRC.