Barley, Hordeum vulgare L., is among the oldest cultivated crops dating 5000 to 7000 years B.C. (Clark 1967; Harlan 1976, 1979) and perhaps much older (Wendorf et al. 1979). Barley has also been a favorite genetic experimental organism since the rediscovery of Mendel’s laws of heredity (Tschermak 1901; cited from Smith 1951). The widespread use of barley is attributable to its diploid nature (2n = 2x = 14), self fertility, large chromosomes (6–8 μm), high degree of natural and easily inducible variation, ease of hybridization, wide adaptability, and relatively limited space requirements. The early literature on the genetics of barley and related information has been reviewed (Smith 1951; Nilan 1964, 1974; Briggs 1978) and more recently in Rasmusson (1985) and Shewry (1992). A comprehensive listing and description of the genes known at the time can be found in Sogaard and von Wettstein-Knowles (1987), updated by Von Wettstein-Knowles (1992). Periodic publications such as the Proceedings of International Barley Genetic Symposia (Lamberts et al. 1964; Nilan 1971; Gaul 1976; Asher et al. 1981; Yasuda and Konishi 1987; Munck 1992) and the annual Barley Genetics Newsletter (since 1971) summarize and update the barley genetic literature.