The hemostatic valve assembly (10) includes a housing (14) with a chamber (16) therewithin. A flexible valve element (26) is located in the chamber (16) and supported by the housing (14). A source (28) of pressurized fluid can be fed into the chamber (16) through a port (18) in the housing (14). A catheter, dilator and pusher or other elongate insert fed through the hemostatic valve assembly (10) can be sealed by the application of fluid pressure into the chamber (16), which causes the sides of the valve element (26) to press against the insert (24) thereby to provide an effective seal.
