A needle shroud assembly 10 comprises a barrel 16, a needle shroud 18 captively telescoped relative to the forward end of the barrel for movement between retracted and extended positions and is biased towards said extended position by a spring 25. A separate locking element 42 is mounted within the barrel moveable between a safe position (as seen in Figure 5) in which it prevents or limits retraction movement of said needle shroud 18, and a live position in which it is clear of the rearward path of the needle shroud 18. The locking member is moved from its safe position to its live position by means of an externally operable actuating member 54, having a cam 52 which cooperates with a cam surface 46 on the locking element 42. The cam 52 is driven back to its original position by the rearward end of the shroud 18 as it moves to the fully retracted position.
