The Gould Laboratory studies vesicles, known as exosomes and microvesicles (EMVs), that can be taken up by neighboring cells, completing a pathway of intercellular vesicle traffic. Our laboratory studies the molecular mechanisms of EMV biogenesis and uptake, and their contributions to cell polarity, cell-to-cell interactions, and intercellular signaling. We also examine the ways in which HIV and other retroviruses use the exosome biogenesis pathway for the formation of infectious virions, and the consequences of their EMV origin.