To test the suggestion that an enhancement of sputtering occurs in very dense collision cascades, the sputtering yieldper atomwas compared for atomic and molecular ions. In all cases tested, the yieldper atomwas higher for the molecular ions. This effect is the more pronounced the heavier the projectile and the target. In the molecular cases the overlapping cascades have higher energy densities than those initiated by the atomic ions; our results, therefore, support the suggestion of a sputtering enhancement in dense cascades.