594840 Disclosed is an apparatus and method for fumigating an enclosed space. The apparatus (10) comprises a flexible enclosure (12") that is inflatable and deflatable with a gaseous fumigant between an expanded configuration and a collapsed configuration. The flexible enclosure is positioned within the enclosed space prior to fumigant introduction. When the flexible enclosure is inflated, and subsequently expands, it displaces a volume of gas from the enclosed space. The apparatus also comprises an inlet (16) to receive gaseous fumigant for inflation of the flexible enclosure, as well as an outlet (20") and a valve. The valve opens and closes the outlet to release the gaseous fumigant from the enclosure via the outlet and into the enclosed space. A method for fumigating an enclosed space is also disclosed.