Millions of people in Southwestern Bangladesh drink groundwater that has arsenic contamination levels above both Bangladeshi and WHO standards. Thus, arsenic, the king of poisons, presents significant social problems in the rural communities of Bangladesh. Lacking arsenic-free drinking water, the local populations are most adversely affected. Arsenic contamination of drinking water and food is the main pathway by which arsenic enters people's lives, producing diseases such as melanosis, keratosis, skin lesions, skin cancers, and kidney failure. Therefore, to cope with and alleviate arsenic poisoning, whatever adaptation and mitigation strategy is adopted, it should, however, start with and be led by the local community wherever possible for it is local villagers who are often the real experts on arsenic contamination. Rather than implementing highly technical, expensive, and outsider-led interventions that are often untried in field conditions, priority should be given to using modified traditional coping and mitigation mechanisms developed in the communities in Bangladesh. Hence, this chapter highlights first the extent of arsenic poisoning in the Southwestern part; its adverse impact on livelihood, water sector, and social aspect; and then the focus shifts to community-level mitigation strategy led by the people along with the assistance of GO and nongovernmental organization (NGO); and finally there is the conclusion along with recommendations.