An analysis is made of the effect of dislocation vibration on the efficiency of a dislocation line as a sink for point defects. It is concluded that a dislocation will act as a better sink whenever the amplitude of vibration A is larger than the characteristic diffusion distance d = (D/4v)1/2wherevis the frequency of vibration andDis the diffusion coefficient of the point defect. BecauseDis so large for interstitial atoms it is not expected that this effect ever is important for interstitial atoms. The effect can be important for lattice vacancies and can counteract the effect of the stress field of a dislocation that makes a dislocation line a more efficient sink for interstitial atoms than for vacancies. The present theories of void growth in irradiated metals depend on the assumption that dislocation lines are better sinks for interstitials than for vacancies. If these theories are correct, then one can expect that void growth can be prevented by vibrating dislocations over a great enough amplitude at a high enough frequency.