Abstract: The present disclosure provides valve assemblies arranged for penetrating a membrane on an outlet port of a container, such as an intermediate bulk container. In some aspects, the valve assembly comprises a moveable plunger with a membrane penetrating portion that, after the valve assembly has been coupled to the container, is selectively operable to penetrate the membrane of the container. Alternatively, the plunger may be configured to an extended configuration prior to attachment of the valve assembly to the container so that as the valve assembly is coupled to the container, the plunger penetrates the membrane of the container. Other arrangements and methods of using the same are disclosed.