Abstract: Apparatus and methods for performing vasectomies are disclosed. In preferred embodiments, a clamp has a set of jaws, the distal ends of which terminate in a circular structure that is essentially a split ring. In certain embodiments, each jaw has a serrated edge that corresponds to serration on the opposite jaw, and each jaw is slightly less than a half-circle so that when closed there is a small slot or opening toward the handle side of the jaws. The jaws are adapted to grasp the vas of a patient and the slit permits a scalpel blade to cut the vas sheath longitudinally in the clamped region. Alternatively, the serrated jaws can be replaced by a single tooth on each arm of the clamp, and these teeth overlap, again leaving a single slot. Finally, in certain other embodiments, the distal ends are hooked structures and remain spaced apart even when the clamp is in the closed position.