Community monitoring can track environmental phenomena, resource use, and natural resource management processes of concern to community members. It can also contribute to planning and decision-making and empower community members in resource management. While community monitoring that addresses the environmental crisis is growing, it also gathers data on other global challenges: climate change, social welfare, and health. Some environmental community monitoring programs are challenged by limited collective action and community participation, insufficient state responsiveness to data and proposals, and lack of sustainability over time. Additionally, community members monitoring the environment are increasingly harassed and sometimes killed. Community monitoring is more effective with improved data collection, improved data management and sharing, andstronger efforts to meet community information needs, enable conflict resolution, and strengthen self-determination. Other promising areas for development are further incorporating governance issues, embracing integrated approaches at the community level, and establishing stronger links to national and global frameworks.