This interdisciplinary book brings philosophers and non-philosophers to the table to address questions of water ethics, specifically in terms of how moral questions inform decision making around water security at local, national, and international scales. Water security, which pertains to the experience of assured access to clean water, is a broad concept that intersects human rights, politics, economics, law, legislation, public health, trade, agriculture, and energy. Decisions made at each of these intersection points have ramifications for human well being, especially for the populations that are marginalized in a societal and political sense. In this book, the ethical dimensions of decision-making at those intersection points are explored, and real-world examples are used to tease out some key insights. It charts how ethical consideration can help shape a future in which everyone will be water secure.