Rural residents photograph ailing chickens to monitor the spread of Avian flu, mountaineer adventurers collect scat samples so microbes in isolated locations can be identified, and sailors take water samples that reveal the plastic afloat in the world’s oceans. These citizen scientists are ordinary people who collect data in the field that support researchers warning of disease outbreaks, studying the origins of antibiotic resistance, assessing pollution levels, and tracking community health. There’s nothing amateurish about their efforts – these cost-effective partnerships lead to genuine scientific discoveries. What can we learn from this kind of crowd-sourced data?