Beetle species belonging to the coleopteran families Bruchidae, Curculionidae, Laemophoeidae, Silvanidae and Tenebrionidae, as well as beetle-like insects from the psocopteran family Liposcelidae, are responsible for serious damages to agricultural products and resources. These beetles can be primary and/or secondary pests, feeding on integral and healthy grains or attacking those already damaged. The affected grains lose weight and germination power, have nutritive value and vigor decreased, as well as have the hygiene and sanity conditions impaired. This book examines the biodiversity, ecology and role in the environment of beetles.