Retrospective and prospective studies were used to assess the numbers, types and persistence of microbes that contaminate wind instruments. All previously played instruments (n = 20) harbored viable bacteria as well as mold and/or yeast. Reedinstruments consistently carried higher microbial loads than did flutes or trumpets. Instruments played within the previous three days bore typical mouth flora, while bacteria recovered after 72 h following play consisted of normal environmental flora. Prospective studies tested survival of potentially pathogenic bacteria (Staphylococcus, Streptococcus, Moraxella, Escherichia coli and attenuated Mycobacterium tuberculosis) when applied to reeds or following simulated 'play' of a clarinet. All species survived for a maximum of 24-48 h on reeds, except Mycobacterium, which persisted through 13 days. In simulated play experiments, test bacteria could persist for up to five days. These findings support the establishment of guidelines for decontamination of wind instruments and for sharing or transfer of these instruments among players.