Well-structured schemes for citizen scientists can minimize the potential for conflicts of interest (Nature 524, 265; 2015).

Projects such as the UK Breeding Bird Survey (go.nature.com/keyvpu), run by the British Trust for Ornithology, use volunteer-friendly protocols and specify sampling at representative locations to standardize volunteer commitment. The primary motivator for observers is then whether to invest and participate in the survey, not whether they can influence which data are recorded.

Citizen scientists participating in well-structured schemes are more likely to deliver cost-effective monitoring on a large scale and to improve societal understanding of scientific issues.