Aspergillus fumigatus is a dangerous fungal infection treated with triazole drugs, but the fungus is developing resistance to multiple antifungal medications. This resistance appears to be selected in agricultural settings where fungicides are used on crops, and resistant strains then spread to humans through the air. The problem is worse because agricultural fungicides are selecting for strains resistant to multiple drug classes at once, making infections harder to treat. Addressing this issue requires reducing fungicide use in agriculture and better strategies for managing antifungal resistance.