The use of silver to control putrefaction of liquids and as a mitigate to the incursion and spread of disease can be traced to ancient times. In recent decades, studies have revealed the biochemical reactions of ionic silver that result in the inactivation of bacteria, fungi, protozoa, spirochetes, viruses, etc. not protected by proteinaceous membranes. The unique chemisorption of atomic oxygen on the surface of silver in both gaseous and aqueous media combined with freedom of movement of oxygen throughout the crystal lattice of the silver provides a reservoir of oxygen and thus sets silver apart in its catalytic activity. Studies have revealed that bulk silver in an oxygen-charged aqueous media will catalyze the complete destructive oxidation of microorganisms. However, the broad use of silver as a powerful clinical tool is still in the future because its full range of activity remains to be elucidated.