Over the last 30 years, disaster management has experienced a ‘participatory turn’, in which the centrality of community participation and volunteerism has been rediscovered within academia and governments around the world. This chapter reviews current knowledge of disaster volunteerism and community participation in managing environmental hazards. It first describes the broad ecosystem of disaster volunteerism and community participation, emphasising the diversity of form and function. After positioning the concepts of ‘community participation’ and ‘volunteerism’ and summarising some of the conceptual foundations for understanding them, it considers four important themes in contemporary research: the impact of new communications technology and digitally enabled volunteering; integration and coordination of ‘outsider’ volunteers; sustainability of formal disaster response volunteerism; and implementing community-based disaster risk reduction. Finally, the chapter highlights five outstanding gaps in knowledge for future research to tackle.