SI2-SSI: - Advancing and Mobilizing Citizen Science Data through an Integrated Sustainable Cyber-Infrastructure is a citizen science platform that advances the impacts and outcomes of field-based projects. We allow projects to create their own projects in a do-it-yourself approach. Projects can define what they wish to measure, document how they measure it, and build custom datasheets for real-time data entry online and via mobile applications. This saves projects the costs and hassles associated with creating their own front-end and back-end systems and custom mobile apps. provides an integrated suite of volunteer management capabilities plus data exploration and visualization tools for people to create their own visualizations of trends, relationships, and comparisons. Tools exist for communications, alerts, uploading data, and custom downloads. In contrast to most systems, we support structured observations – rigorous protocols for observing natural phenomena that follow experimental designs enabling statistically significant scientific comparisons. We facilitate cross-project sharing of protocols, measurement, data, and ideas for meta-analyses and interoperability.