Ethics (or ethic) is the discipline that includes a set of moral principles, which enable human beings to take decisions about what comprises right or wrong behavior. Ethical theory has three main branches: metaethics, which tries to define the basis of right behavior; normative ethics, which prescribes what constitutes right behavior; and applied ethics, which deals with specific issues to take the best possible ethical decision. Again, ethics could be categorized into virtue ethics; deontological or duty-based ethics, which is a non-consequentialist ethics; and utilitarian ethics, which is a consequentialist one. The Greek naturalist-philosopher Aristotle’s ethics were based on eudaimonia, which connotes happiness or flourishing. Environmental ethics tries to determine the rightness or wrongness of human actions that can affect the environment and its myriad living and non-living components. Environmental ethics comprises anthropocentric or human-centered, biocentric or life-centered, and ecocentric or ecosystem-centered approaches. Anthropocentric ethics recognizes intrinsic values in human beings alone, while biocentric ethics recognizes this value in all living beings, including non-humans, and ecocentric ethics recognizes it in entire ecosystems. Many general ethical principles such as beneficence, maleficence, informed consent, the precautionary principle, and others are also applicable to environmental ethics and water ethics.