A dispenser closure suitable for use with bag-in-box type packages comprising a spout (11), a valve seat (28), a valve member (22) projecting from one face of a substantially concave diaphragm (25) so that the diaphragm urges the valve member into closing contact with the valve seat and a pull-tab (27) projecting from the other face of the diaphragm to enable the valve member to be withdrawn from the seat. A skirt (14) projects below the valve seat and flow directing vanes (20) may be provided within the skirt. An embodiment suitable for use with aerated beverages including beer is also disclosed together with a filling head to be used in conjunction with the closure.