Convenience kits designed to provide for closed, but selectable liquid transfer from a vial to a variety of IV containers and medical syringes. In particular, a kit for fully enclosing a vial for safety in hazardous drug transfer is disclosed. Generally, the kits contain unitized parts wherever reasonable to limit makes and breaks. Further, pathway determining kits provide selectable pathways for purging connections wish flushing solution where makes and breaks are made between various fluid pathway involved parts such that, when disconnections are made, flush solution is resident at the exposed interface. Also disclosed is a 3-way valve as part of a closed, switchable pathway controlling subsystem by which pathways are selected for reconstituting dry medicine in a vial, displacing a measured dose of liquid from a vial, exchanging gas into the vial for displaced liquid, delivering the measured dose to an IV container.