In this chapter, arsenic-accumulating and arsenic- transformingbacterial strains that can be employed as a sourcefor cost-effective and eco-friendly bioremediation of arsenicsfrom contaminated environments have been reviewed. Thischapter demonstrates that many naturally occurring bacterialstrains like B1-CDA have the potential for reducing arseniccontent in contaminated sources to safe levels. Therefore,the socioeconomic impact of this kind of microorganisms ishighly significant for those countries, especially in the developingworld, where impoverished families and villages aremost impacted. Therefore, this discovery should be consideredto be the most significant factor in formulating nationalstrategies for effective poverty elimination. Besides humanarsenic contamination, these bacterial strains will also benefitlivestock and native animal species, and the outcome ofthese studies is vital not only for people in arsenic-affectedareas but also for human populations in other countries thathave credible health concerns as a consequence of arseniccontaminatedwater and foods.