In ancient times, people practiced cleanliness often for religious reasons. In the Greek period the idea that human health is related to the physical environment developed. The notion that microscopic organisms might cause infectious diseases begun to take shape in the 16th and 17th century. Nowadays hygiene concentrates on manipulating and controlling the environment for the benefit of human health. In household and institutional practice, hygiene is mainly dedicated to the control of micro-organisms in the inner environment. Household cleaning plays an important role in establishing and maintaining an adequate level of hygiene. In cleaning research therefore substantial attention is paid to the interrelation between cleaning and removal of micro-organisms. In general a worse soil removal appears to lead to a lower level of hygiene. In the past decades technical measures to reduce the environmental impact have affected household and institutional cleaning processes. In several ways this has degraded the level of cleaning and indirectly the level of hygiene. In the future more environmental measures that may affect the level of hygiene are to be expected. Scientists and professionals dealing with hygiene should be aware of these phenomena and should search for cleaning processes that are for use, sustainable and that do not endanger the level of hygiene.