Barley (Hordeum vulgare L.) is a cereal crop belonging to the grass family of Poaceae. It represents one of the world’s oldest cultivated grains, dating back around 13000 years ago in Eurasia. Along with wheat, corn and rice, barley is one of the world’s most important crops, according to the U.S. Grains Council. Barley has played an important role in plant genetics and breeding, plant physiology, agronomy, cereal chemistry, human and animal nutrition, plant pathology, and entomology. Barley, as an experimental organism, has contributed to the development of scientific knowledge, and science has contributed to the improvement of barley as a crop. Barley, as the fifth most - produced crop in the world today, involves massive amounts of resources and people working in production agriculture; commodity transportation. This cereal grows in temperate climates, thus being cultivated worldwide, especially in Europe, North Africa, Russia, Canada, and Australia. Barley is widely used for several purposes, including food, beverages, brewing, animal feed, medicinal plant and as a model organism in molecular research. Interests in barley production and use continue to grow, causing a need for an up-to-date review of works related to the recent state-of-the-art of barley’s production field. In this book, latest papers about barley cultivation, including improvements in production, selection and uses, are collected. In particular, the first couple of works report the effect of specific conditions on barley production, such as warming, genetic drift and exposition to nanoparticles. Then, genetic characterization, resistance and biochemical studies from seeds’ germination to maturation are proposed. Moreover, some genomics, transcriptomics and proteomics papers about barley improvement have been selected. Finally, a very innovative use for transgenic production of anti-HIV antibodies in the barley endosperm is presented. Providing comprehensive information on topics ranging from fundamental aspects to specific applications, this book offers a useful resource for scientists, plant breeders, teachers and advanced students in the fields of molecular and plant cell biology, plant biotechnology, and agronomy.