In a public sauna a considerable germ level was found to exist in all areas during rush hours. Although no specifically pathogenic germs were detected on the surfaces, the existence of E. coli would suggest that particular attention must be given to the hygiene of this type of bathing establishment. It is particularly important that the relatively high temperatures in the heated area of the sauna do not cause a hygienically decisive germ reduction. Apart from this, especially the foot-warming basins appear to be undesirable germ reservoirs, even for pathogenic germs (Staph, aureus, P. aeruginosa). Systematic daily disinfection, which is recommended as a basic requirement but which in practice is mostly omitted, proves indispensable. Proper use of the relatively harmless hydrogen peroxide allows the hygienic conditions to be clearly improved, shortly.