South America is fighting a battle against tiger mosquitoes that transmit yellow fever, dengue fever and the Zika virus. In Central Europe, wine and fruit growers fear another year of massive crop failures due to a type of vinegar fly known as the spotted-wing drosophila. Since the success rate of conventional methods continues to fall, Fraunhofer researchers in Gießen are developing new species-specific strategies that keep pests under control without resorting to environmental toxins.