One of the key constraints to improving food and nutritional security in the developing world is poor post-harvest management, which leads to loss of grains. Improved post-harvest management at farm level is crucial, as it directly impacts on poverty alleviation, food, nutrition and income security, and prosperity for smallholder farmers. This chapter begins with an overview of post-harvest losses in maize, reviewing the prevalence and significance of the problem, as well as the types and causes of losses. It then considers the biological and socio-economic causes of post-harvest losses. Finally, we offer a discussion of how post-harvest losses can be avoided through technological interventions