Citizen science and community-based monitoring programs are increasing in number, breadth, and popularity. These programs operate at multiple spatial and temporal scales and ask questions that relate to myriads of issues, such as biodiversity, environmental quality, and climate change. Citizen science groups involve numerous stakeholders who generate volumes of diverse scientific data including species observations (e.g. Pika abundance) and site characteristics (e.g. stream pH).  The majority of programs are bottom-up, grassroots efforts with conservation biology-oriented goals and objectives. To be effective, such programs must train and manage members, design protocols, collect data, share results, and evaluate success. On face value, these tasks may seem simple, focused on questions of interest to each program.  In reality, information generated about the world around us is an asset to broader society and of use to land managers, conservation biologists, policy makers, and educators. Given this, we developed CitSci.org - an open and comprehensive, rigorous, web-based cyber-infrastructure for citizen science programs (www.citsci.org).  We implemented a full spectrum of features designed to support communication with members, plan and document data collection metadata, manage data organization and quality, standardize data measurements, units, and protocols, and analyze and visualize information. CitSci.org empowers program coordinators to create their own projects, manage and communicate with members, build their own custom data sheets, streamline data entry, visualize data on maps, edit data values, and automate custom analyses. Thus far, CitSci.org has engaged 97+ programs resulting in some 28,191+ species observations and 53,211+ site characteristics. Here, we discuss the unique challenges and opportunities afforded by the CitSci.org platform to support the needs of citizen science, community based monitoring, and other scientific research projects to participate in rigorous science.