This case study, the first of a two part series, is derived from the experience of the Community-Based Flood Mitigation and Preparedness Project (CBFMP) (1998-2001). It features the development of an organizational framework for flood vulnerability reduction in 23 Cambodian villages. The step-by step process by which this was achieved involved: (1) selecting project sites, targeting most vulnerable communities (2) selecting community members as volunteers and training them to work with communities in reducing vulnerabilities; (3) organizing communities and establishing Community-Based Disaster Management Committees (CBDMCs) as a coordinating body; and (4) identifying, estimating and ranking local disaster risks through risk mapping. Building the capacities of communities to mitigate, prepare for and respond to disaster in a self-reliant and cooperative manner is emphasized.