A fitment for a package holding a liquid therein, said fitment being configured for selectively dispensing a quantity of the liquid from the package, the package comprising a flexible bag having a hollow interior, in which the liquid is disposed and a wall contiguous with the hollow interior, said fitment comprising: a body having a portion configured for securement to the wall of the bag, a passageway, and an outlet port in communication with said passageway; an actuator comprising a member configured to be repeatedly depressed and released; and a piercing member being configured to be moved in one direction through said passageway and through a penetration zone of said wall of said bag contiguous with said hollow interior to an extended position upon the depression of said actuator and moved in a second and opposite direction back through said wall of said bag and through said passageway to a fully retracted position in automatic response to the release of said actuator, characterized in that said piercing member comprises a hollow cylindrical section having an outer surface and being coupled to said actuator, and one of said passageway and said outer surface of said hollow cylindrical section of said piercing member comprising at least one annular seal (170, 172), said outer surface of said piercing member and said at least one seal (170, 172) forming a fluid tight interface therebetween, said piercing member including a portion blocking said outlet port when said piercing member is in said fully retracted position, and unblocking said outlet port when said piercing member is moved to said extended position, thereby enabling the liquid within the hollow interior of the bag to flow out of the bag through said hollow cylindrical section of said piercing member and said passageway to said outlet port. a body having a portion configured for securement to the wall of the bag, a passageway, and an outlet port in communication with said passageway; an actuator comprising a member configured to be repeatedly depressed and released; and a piercing member being configured to be moved in one direction through said passageway and through a penetration zone of said wall of said bag contiguous with said hollow interior to an extended position upon the depression of said actuator and moved in a second and opposite direction back through said wall of said bag and through said passageway to a fully retracted position in automatic response to the release of said actuator, characterized in that said piercing member comprises a hollow cylindrical section having an outer surface and being coupled to said actuator, and one of said passageway and said outer surface of said hollow cylindrical section of said piercing member comprising at least one annular seal (170, 172), said outer surface of said piercing member and said at least one seal (170, 172) forming a fluid tight interface therebetween, said piercing member including a portion blocking said outlet port when said piercing member is in said fully retracted position, and unblocking said outlet port when said piercing member is moved to said extended position, thereby enabling the liquid within the hollow interior of the bag to flow out of the bag through said hollow cylindrical section of said piercing member and said passageway to said outlet port.