A vacuum demand valve (10) is capable of delivering a flowable material. The valve (10) has a housing (11) having a proximal end (14), a distal end (16), an intermediate segment (18) therebetween defining a passageway (24) wherein the flowable substance can flow from the proximal end (14) to the distal end (16). The housing (11) can be tubing. A valve member (20) is located along the intermediate segment (18). The valve member (20) has a closed condition wherein the flowable material from the proximal end (14) to the distal end (16) is stopped and an open condition wherein the flow of the flowable material from the proximal end (14) to the distal end (16) is unstopped. The valve member (20) is biased in the closed condition and is responsive to a partial vacuum provided by the user through the passageway (24) for placing the valve member (20) in the open condition.