Abstract: An isolator system 10 comprises an isolator 11 moveably mounted on a support 12 and an impervious bag 16 open at one end and sealingly attachable to the isolator 11. A drum 90 containing a substance to be dispensed may be sealingly attached to the isolator by moving the isolator to the drum. The lid 110 of the drum 90 may be removed from the drum once the lidded end of the drum is within the isolator 11. The isolator is able to rotate about the axis of its support which causes inversion of the isolator and the drum now contained within the isolator. Substances contained within the drum may be dispensed into a second container such as an IBC whilst contained within the enclosure thus protecting an operator from contamination from the substance.