The mollusk collection at the University of Michigan Museum of Zoology, by its size and past and present significance is a major national and international resource. Its importance as a reference collection in freshwater biology, invertebrate zoology, medical and veterinary zoology, and paleontology lies in the fact that it contains one of the largest collections of freshwater mollusks in the world. The division also has a respectable marine collection, and a land snail collection that has been the basis of numerous doctoral theses. In regard to land snails, it is one of the top collections in the United States. The mollusk division collection contains over 250,000 cataloged lots of dry specimens (approximately five million specimens), at least 5,000 uncatalogued lots of wet specimens (mostly ethanol preserved), and sizable collections of radulae, molluscan antisera and antigens, etc.

The excellence of its collections and library have enabled the Mollusk Division to provide many services to the scientific community. These include loaning specimens, providing facilities, making identifications, collaborating with state, federal and international agencies in regard to conservation, health, and other concerns, and in generating basic data and new research techniques for scientific advancement in malacology. The Museum of Zoology has long been one of the major molluscan research centers in the world, and has trained a significant number of the United States' malacologists. Its mollusk collection has played an important part in the doctoral theses of these specialists, and, in turn, these students often have added substantially to the collection. Because of the Mollusk Division's active research programs, specimens from all over the world continue to arrive. It is this process that allows the division to continue in its effort to provide information and facilities to researchers, educators, resource managers and many others.