This paper discusses community participation drawing on ongoing disaster risk reduction and climate change adaptation projects in the communities affected by the Heavy Rain Event of 2018 in western Japan. By ‘DRR’, the paper supports the perspective of ‘DRR including CCA’. ‘Participatory’ approaches have become a mainstream methodology for community-based DRR as advocated in the Sendai Framework for Disaster Risk Reduction. The existing participation literature addresses either the types of participation or ‘success’ factors for participation. The paper proposes there is also a challenge of ‘widening participation’, particularly in the initiatives that are already recognised as ‘good practices’. Originally widening participation was a higher education policy in the UK aiming to broaden the demographic composition of the student base. Borrowing this notion, the paper identifies how each project encourages non-participants to get involved in the project activities. The paper also draws on machizukuri [community development], which has increasingly become an overarching social policy integrating health, welfare, education and DRR. Participation is emphasised as a requisite of machizukuri in developing a resilient and sustainable community and ultimately, a democratic society.