Corn is a major source of food and feed but is limited in its nutritional value, most notably because of its low lysine content. Although the isolation of high lysine corn lines through genetic screens were successful, the pleiotropic effects associated with the high lysine traits makes it difficult for integration into a commercial breeding program. With the advancement in biotechnology, alternative strategies for enhancing lysine content in corn have been explored. The progress of these genetic engineering approaches will be summarized and discussed within.