Egalitarianism is a political doctrine that holds that all people should be treated as equals from birth, usually meaning held equal under the law and in society at large. It is a belief in human equality, especially with respect to social, political and economic rights and privileges, and advocates the removal of inequalities among people and of discrimination (on grounds such as race, gender, sexual orientation, religion, etc).

Political philosophies such as Socialism, Marxism, Communism and Anarchism all support the principles of Egalitarianism to some degree. Some argue that modern representative democracy is a realization of political Egalitarianism, while others believe that, in reality, most political power still resides in the hands of a ruling class, rather than equally in the hands of the people. For example, the United States Declaration of Independence of 1776 includes a kind of moral and legal Egalitarianism in its assertion that "all men are created equal" (and therefore that each person is to be treated equally under the law), but it was not until much later that U.S. society extended these benefits to slaves, women and other groups. The motto of the French Revolution of 1789, "Liberté, égalité, fraternité", was only really institutionalized during the Third Republic at the end of the 19th Century.

The term is derived from the French word "égal", meaning "equal" or "level", and was first used in English in the 1880s, although the equivalent term "equalitarian" dates from the late 18th Century.

• Economic Egalitarianism (or Material Egalitarianism) is where the participants of a society are of equal standing and have equal access to all the economic resources in terms of economic power, wealth and contribution. It is a founding principle of various forms of Socialism.

• Moral Egalitarianism is the position that equality is central to justice, that all individuals are entitled to equal respect, and that all human persons are equal in fundamental worth or moral status.

• Legal Egalitarianism the principle under which each individual is subject to the same laws, with no individual or group or class having special legal privileges, and where the testimony of all persons is counted with the same weight.

• Political Egalitarianism is where the members of a society are of equal standing in terms of political power or influence. It is a founding principle of most forms of democracy.

• Luck Egalitarianism is a view about distributive justice (what is just or right with respect to the allocation of goods in a society) espoused by a variety of left-wing political philosophers, which seeks to distinguish between outcomes that are the result of brute luck (e.g. misfortunes in genetic makeup, or being struck by a bolt of lightning) and those that are the consequence of conscious options (e.g. career choices, or fair gambles).

• Gender Egalitarianism (or Zygarchy) is a form of society in which power is equally shared between men and women, or a family structure where power is shared equally by both parents.

• Racial Egalitarianism (or Racial Equality) is the absence of racial segregation (the separation of different racial groups in daily life, whether mandated by law or through social norms).

• Opportunity Egalitarianism (or Asset-based Egalitarianism) is the idea that equality is possible by a redistribution of resources, usually in the form of a capital grant provided at the age of majority, an idea which has been around since Thomas Paine (1737 - 1809).

• Christian Egalitarianism holds that all people are equal before God and in Christ, and specifically teaches gender equality in Christian church leadership and in marriage.