Two crucial aspects of transport vesicle function have recently been reconstituted using purified proteins and chemically defined lipid bilayers. The reconstituted steps are the assembly of a polymeric protein coat on the cytosolic surface of the membrane, and bilayer fusion based on the pairing of proteins in the vesicle and target membrane. These advances now set the stage to address major unresolved questions of how vesicle budding and vesicle fusion are regulated, how specific cargo molecules are incorporated into vesicles, and how vesicles find their target membrane.