According to the invention, a safety device for a pre-filled syringe comprisesa hollow support body for retaining the pre-filled syringe,a hollow needle shield that is movable relative to the support body from a first position to a second position,releasable mounting means to mount the pre-filled syringe within the support body anda spring means arranged within the support body in a non-energized or only slightly energized state.The movement of the needle shield from the first position to the second position fully energizes the spring means.
