This report assesses the impact ofparticipation in farmer organizations (FOs) on food securityof rural households in Cambodia. The study is particularlyset out to following: (1) examine FOs’ roles and operationand challenges for improving household’s food security; (2)analyze household’s characteristics that determineparticipation in FOs; (3) assess the impact of FOs on foodsecurity and livelihood of the rural poor; and (4) providespecific recommendations for changes in relevant legal actsand regulatory frameworks associated with FOs. The studyconcentrates on three types of FOs based on theirpredominance in Cambodia. Farmer groups (FG) are informalgatherings with 10-30 members. Farmer associations (FA) havemore than 30 members and can either be informal or formal ifregistered at the Ministry of Interior. Agriculturalcooperatives (AC) are business oriented, registered at theprovincial department of agriculture (PDA) and comprisegenerally more than 30 members. This report is structured asfollows: section one gives introduction. Section two reviewsinternational as well as Cambodia’s experiences in farmerorganizations to promote rural livelihoods and agriculturaldevelopment. Section three details the research methodologyemployed in this impact assessment. Section four presentsthe detailed empirical findings. Section five concludes thereport with a summary of the policy implications and recommendations.