In this paper, we explicate citizen science in information systems research. Citizen science in IS research is a partnership between IS researchers and people in their everyday lives. Citizen science projects in the IS field are defined by phenomenon that interest both citizens and scientists and by the intervention of citizens in scientific processes for the purposes of scientific literacy and a more informed citizenry. We make the case for citizen science as part of a movement in IS research towards societally impactful research at the confluence of human behavior, technology, society, and environmental sustainability. We discuss the origins of citizen involvement in science and contemporary notions of citizen science from sociological, natural science, and public policy perspectives to build a working definition for the IS field. We provide examples of how one can leverage citizen science in IS research and discuss larger ideas for the possibility of citizen science.