It is estimated that approximately 300 million people worldwide are affected by asthma, and the number of patients affected is growing exponentially-with potential for an additional 100 million people affected by the condition by 2025.1 With this increasing burden of disease, there is high motivation to discover effective prevention strategies. Strategies aimed at stalling the atopic progression, modifying the microbiome, preventing respiratory viral infections, and reducing the impact of toxin/pollutant exposure through dietary supplements have had limited success in the prevention of asthma. This is likely because asthma is heterogenous, and influenced by different genetic and environmental factors. Genes underlie a predisposition to asthma and allergic sensitization, while exposure to allergens, respiratory infections, and pollution may modify asthma pathogenesis and the variation in severity seen among individuals. Future advances in asthma prevention may include a more personalized approach: genetic variations among susceptible individuals with distinct asthma phenotypes, or different biomarkers of disease may help individualize prevention strategies and render them more effective. In this article, we summarize interventions that have been studied for the prevention of asthma and identify some of the clinical trials that are actively underway in asthma prevention.