Conventional marker-assisted and GM breeding contribute to the production of new maize varieties to compete in the complex global agricultural marketplace. Breeders aim to improve quality and yield, create varieties that are suited to particular agricultural practices and raise the nutritional value of maize without compromising high safety standards. This chapter focuses on the diverse methods available for affecting the development and chemical composition of maize kernels, so as to improve their protein and starch content. We summarize the current state of knowledge and technology in this area, with a focus on protein storage, varieties of starch and how to enhance the quality-related traits of maize kernels. We also consider potential future developments in the field and the application of breeding strategies to develop new maize products with higher nutraceutical value and lower levels of anti-nutritional factors such as allergens.