A passive safety device for a medical needle has a mount for supporting the needle and a needle shielding sleeve co-axial with and arranged for sliding movement relative to the mount, from a shielding position to a non-shielding position. An abutment surface is provided on one of the sleeve and mount and is engageable by a radially deformable finger, when undeformed. A control member is also slidably arranged with respect to the mount and sleeve and has an initial set position. The control member co operates with the finger so that on sliding movement of the sleeve from its initial shielding position, the finger is moved radially outwardly, clear of the abutment surface and on to a sliding surface. Continued movement of the sleeve increases deformation of the finger and generates a restorative force between the finger and the sliding surface to move the sleeve back to a needle shielding position following the performance of a procedure and return the finger into radial alignment with the abutment surface, the control member remaining displaced from its set position.
