Technical Abstract: The US National Plant Germplasm System, (NPGS) a group within the Agricultural Research Service of the United States Department of Agriculture, is comprised of over 20 field stations spread throughout the US and is responsible for the preservation and distribution of genetic resources important for food and agriculture. As of July, 2007 the NPGS cosseted of over 475,000 accessions of plant genetic resources which included over 2000 genera and 12,000 species of plants. The National Center for Genetic Resources Preservation, with over 700,000 collections of plant genetic resources houses the base collection for the NPGS as well as acts as a back-up repository of plant genetic resources for other national and international entities. While the vast majority of the collections are seed-based, there is a large group also working on the cryopreservation of vegetatively-propagated crops principally from in vitro shoot tips and dormant woody buds. Methods for storage of both types of plant genetic resources are discussed. These preservation efforts are critical to continued global food security and therefore, the NPGS supports, through collaborations and other efforts to ensure our plant genetic resources are available as a global good.