The most important practice that ethnological museums should adopt is to clean every item as it is accessioned, both to remove the cause of deterioration and to protect the collection from contamination. Fumigation, using para dichlorobenzene crystals or carbon disulphide, is described, and methods of repairing and cleaning which may be practiced by the personnel of small museums are outlined. Leather and buckskin; fur and feathers; bone; ivory and wood; textiles; basketry; metals and their alloys; stone and pottery are among the materials discussed. Procedures which are more complicated should be referred to experts.