The Barley Genetic Stock Collection, including various mutants and aneuploid stocks, is stored at the USDA-ARS National Small Grains Germplasm Research Facility (NSGGRF) at Aberdeen, ID. Each genetic stock is assigned a Genetic Stock Hordeum (GSHO) number as its primary identifier. A total of 2,538 GSHO numbers have been assigned. New accessions recently obtained from North Dakota, Arizona, and Sweden were also included. Many of the stocks are grown in the field every three or four year period for seed increase. Those which do not grow well in the field are grown in the greenhouse or in growth chambers. For aneuploid stocks, seeds are germinated in germination boxes and cytologically checked before planting in the greenhouse for seed increase. Harvested seeds are stored in a cold room at 7-8 C and 22 percent humidity. Ten grams of each genetic stock are sent to the USDA-ARS-NSSL for long term storage. Seed of the barley genetic stocks is freely distributed to interested researchers. Information about the Barley Genetic Stock Collection is available through the Internet at www.ars.usda.gov/PacWest/Aberdeen or www.ars-grin.gov (GRIN), and also in the Barley Genetics Newsletter, Volume 26, 1996.