As ecological and environmental issues become increasingly global, the scientific community is in need of new strategies for conducting and coordinating research at an unprecedented scale. At the same time, such global issues must be understood and addressed by citizens and decision makers at the local level. Citizen science, the practice of involving volunteers in the process of research, is a powerful tool with the potential to increase knowledge in the spheres of both science research and scientific literacy.

The public can be a tremendous aid to scientists engaged in scientific and environmental monitoring and, sometimes, even experimentation. At the same time, the need to increase public understanding of ecological and scientific processes is well documented. A survey of existing citizen science projects indicates that scientists are more deeply involved in citizen science than previously thought (over 30% of responding projects are housed in research and management agencies, and over 20% of project leaders identify themselves as scientists). Furthermore, responses highlight the isolation of practitioners and the need for shared resources in support of goals for both scientific and educational outcomes.

Building on survey results, input from diverse practitioners, and years of experience with citizen science at the Cornell Laboratory of Ornithology, we have developed a theoretical model for citizen science. We present this model in the context of developing NSF-funded resources (a Citizen Science Toolkit) to support emerging and existing citizen science projects.