Technical Abstract: This is an invited article for a free science library and personal training tool sponsored by Nature Publishing Group, which will be included under the topics Agriculture and Biotechnology (http://www.nature.com/scitable). The focus of this article is on Bacillus thuringiensis (Bt) maize. Growers of maize, Zea mays (corn), are challenged with a number of pests, but the most important are lepidopteran larvae (i.e., caterpillars) that are stalk borers, ear feeders, or leaf feeders, and coleopteran larvae (i.e., beetle grubs) that feed on roots. The European corn borer, Ostrinia nubilalis, for example, was nicknamed the "billion dollar bug" because it cost growers over a billion dollars annually in insecticides and lost crop yields. Most maize growers rely on traditional crop protection practices to manage these insects, including cultural, biological, or chemical (insecticide) methods or a balance of these methods that aims to minimize environmental impact called integrated pest management (IPM). However, in 1996, USA growers were introduced to commercial maize that was genetically engineered (GE) with resistance to European corn borer and other lepidopteran maize pests. Bt maize has revolutionized pest control in a number of countries, but there still are questions about its use and impact. This article will focus on the opportunities and challenges presented by Bt maize as they relate to current insect-resistant products. The article will be availble to students, educators, scientists, and growers worldwide.