Technical Abstract: Maize grain infected by Fusarium verticillioides may contain the mycotoxin fumonisin, which is associated with livestock and human diseases. To reduce levels of fumonisin in grain, efforts are underway to identify sources of maize with increased resistance to fungal infection and fumonisin contamination. Field and laboratory techniques have been developed to measure both Fusarium ear rot and fumonisin contamination. Application of these techniques has led to the identification of resistant maize lines and facilitated genetic analysis of resistance to ear rot and fumonisin accumulation. Maize genetics and breeding studies are guiding strategies to improve resistance to fumonisin accumulation.