Animal Hygiene has developed historically from the field of Animal Health Care and is as a part of Veterinary Hygiene now about 100 years old. From her very beginning Animal Hygiene has dealt with the influences of the live and inanimate environment on the health of animals an also investigated the reverse developments. From a historical point of view it can be stated that Animal Hygiene has done active research in the field of environmental hygiene ever since. This tendency was intensified by the modern developments of keeping animals in confinements, enlargement of livestock, new kinds of residues like slurry which demanded a change in the management of arable and forage land combined with an increase in the agricultural utilization of residues form the municipal area like sewage sludge and compost made from refuse. Based on selected examples from the field of production and processing of animals the research on Animal Hygiene in the framework of environmental hygiene is described. This refers especially to emissions and other environmental problems (malodor, dust, airborne microbes) which derive from keeping animals in confinements as well as such which are caused by storage and utilization of animal residues (farm-yard manure, urine, slurry). The most serious problems are caused by production and utilization of slurry (transmission of infectious agents, malodors, damages of soils, plants, surface and ground waters by excess fertilization of arable and forage land). It was Animal Hygiene which made most valuable contributions for solving such problems of environmental hygiene. It was also Animal Hygiene which warned of the possible negative environmental influences of disinfectants. Respective investigations were made and recommendations to avoid damages to the environment given. Also in the field of the agricultural utilization of residues from the municipal area (sewage, sewage sludge, refuse composts) Animal Hygiene has developed basic investigation methods whose results were reflected in several legal regulations for environmental protection.