Normative Ethics (or Prescriptive Ethics) is the branch of ethics concerned with establishing how things should or ought to be, how to value them, which things are good or bad, and which actions are right or wrong. It attempts to develop a set of rules governing human conduct, or a set of norms for action.
		
		Normative ethical theories are usually split into three main categories: Consequentialism, Deontology and Virtue Ethics:
		
		Consequentialism (or Teleological Ethics) argues that the morality of an action is contingent on the action's outcome or result. Thus, a morally right action is one that produces a good outcome or consequence. Consequentialist theories must consider questions like "What sort of consequences count as good consequences?", "Who is the primary beneficiary of moral action?", "How are the consequences judged and who judges them?"
		Some consequentialist theories include:
		Utilitarianism, which holds that an action is right if it leads to the most happiness for the greatest number of people ("happiness" here is defined as the maximization of pleasure and the minimization of pain). The origins of Utilitarianism can be traced back as far as the Greek philosopher Epicurus, but its full formulation is usually credited to Jeremy Bentham, with John Stuart Mill as its foremost proponent.
		Hedonism, which is the philosophy that pleasure is the most important pursuit of mankind, and that individuals should strive to maximize their own total pleasure (net of any pain or suffering). Epicureanism is a more moderate approach (which still seeks to maximize happiness, but which defines happiness more as a state of tranquillity than pleasure).
		Egoism, which holds that an action is right if it maximizes good for the self. Thus, Egoism may license actions which are good for the individual, but detrimental to the general welfare. Individual Egoism holds that all people should do whatever benefits him or her self. Personal Egoism holds that each person should act in his own self-interest, but makes no claims about what anyone else ought to do. Universal Egoism holds that everyone should act in ways that are in their own interest.
		Asceticism, which is, in some ways, the opposite of Egoism in that it describes a life characterized by abstinence from egoistic pleasures especially to achieve a spiritual goal.
		Altruism, which prescribes that an individual take actions that have the best consequences for everyone except for himself, according to Auguste Comte's dictum, "Live for others". Thus, individuals have a moral obligation to help, serve or benefit others, if necessary at the sacrifice of self-interest.
		Rule Consequentialism, which is a theory (sometimes seen as an attempt to reconcile Consequentialism and Deontology), that moral behavior involves following certain rules, but that those rules should be chosen based on the consequences that the selection of those rules have.
		Negative Consequentialism, which focuses on minimizing bad consequences rather than promoting good consequences. This may actually require active intervention (to prevent harm from being done), or may only require passive avoidance of bad outcomes.
		Deontology is an approach to ethics that focuses on the rightness or wrongness of actions themselves, as opposed to the rightness or wrongness of the consequences of those actions. It argues that decisions should be made considering the factors of one's duties and other's rights (the Greek 'deon' means 'obligation' or 'duty').
		Some deontological theories include:
		Divine Command Theory: a form of deontological theory which states that an action is right if God has decreed that it is right, and that an act is obligatory if and only if (and because) it is commanded by God. Thus, moral obligations arise from God's commands, and the rightness of any action depends upon that action being performed because it is a duty, not because of any good consequences arising from that action. William of Ockham, René Descartes and the 18th Century Calvinists all accepted versions of this moral theory.
		Natural Rights Theory (such as that espoused by Thomas Hobbes and John Locke), which holds that humans have absolute, natural rights (in the sense of universal rights that are inherent in the nature of ethics, and not contingent on human actions or beliefs). This eventually developed into what we today call human rights.
		Immanuel Kant's Categorical Imperative, which roots morality in humanity's rational capacity and asserts certain inviolable moral laws. Kant's formulation is deontological in that he argues that to act in the morally right way, people must act according to duty, and that it is the motives of the person who carries out the action that make them right or wrong, not the consequences of the actions. Simply stated, the Categorical Imperative states that one should only act in such a way that one could want the maxim (or motivating principle) of one's action to become a universal law, and that one should always treat people as an end as well as a means to an end.
		Pluralistic Deontology is a description of the deontological ethics propounded by W.D. Ross (1877 - 1971). He argues that there are seven prima facie duties which need to be taken into consideration when deciding which duty should be acted upon: beneficence (to help other people to increase their pleasure, improve their character, etc); non-maleficence (to avoid harming other people); justice (to ensure people get what they deserve); self-improvement (to improve ourselves); reparation (to recompense someone if you have acted wrongly towards them); gratitude (to benefit people who have benefited us); promise-keeping (to act according to explicit and implicit promises, including the implicit promise to tell the truth). In some circumstances, there may be clashes or conflicts between these duties and a decision must be made whereby one duty may "trump" another, although there are no hard and fast rules and no fixed order of significance.
		Contractarian Ethics (or the Moral Theory of Contractarianism) claims that moral norms derive their normative force from the idea of contract or mutual agreement. It holds that moral acts are those that we would all agree to if we were unbiased, and that moral rules themselves are a sort of a contract, and therefore only people who understand and agree to the terms of the contract are bound by it. The theory stems initially from political Contractarianism and the principle of social contract developed by Thomas Hobbes, Jean-Jacques Rousseau and John Locke, which essentially holds that people give up some rights to a government and/or other authority in order to receive, or jointly preserve, social order. Contractualism is a variation on Contractarianism, although based more on the Kantian ideas that ethics is an essentially interpersonal matter, and that right and wrong are a matter of whether we can justify the action to other people.
		Virtue Ethics, focuses on the inherent character of a person rather than on the nature or consequences of specific actions performed. The system identifies virtues (those habits and behaviors that will allow a person to achieve "eudaimonia", or well being or a good life), counsels practical wisdom to resolve any conflicts between virtues, and claims that a lifetime of practicing these virtues leads to, or in effect constitutes, happiness and the good life.
		Eudaimonism is a philosophy originated by Aristotle that defines right action as that which leads to "well being", and which can be achieved by a lifetime of practicing the virtues in one's everyday activities, subject to the exercise of practical wisdom. It was first advocated by Plato and is particularly associated with Aristotle, and became the prevailing approach to ethical thinking in the Ancient and Medieval periods. It fell out of favor in the Early Modern period, but has recently undergone a modern resurgence.
		Agent-Based Theories give an account of virtue based on our common-sense intuitions about which character traits are admirable (e.g. benevolence, kindness, compassion, etc), which we can identify by looking at the people we admire, our moral exemplars.
		Ethics of Care was developed mainly by Feminist writers, and calls for a change in how we view morality and the virtues, shifting towards the more marginalized virtues exemplified by women, such as taking care of others, patience, the ability to nurture, self-sacrifice, etc.