According to Phelps (1987), Distributive justice concerns the nature of a socially just distribution of goods in a society. A society where related inequalities in outcome do not surface would be considered a society guided by the principles of distributive justice. The concept includes the available quantities of goods, the process by which goods are to be distributed, and the resulting distribution of the goods to the members of the society. Distributive justice concentrates on outcomes. (Phelps, 1987)

Distribution in economics refers to the way total output, income, or wealth is distributed among individuals or among the factors of production. Factors included in this are labor, land, and capital (Atkins, Bourguignin, ed., 2000). In general theory and the national income and product accounts, each unit of output corresponds to a unit of income. One use of national accounts is for classifying factor incomes and measuring their individual shares, as in National Income (Atkins, Bourguignin, ed., 2000). But, where focus is on income of persons or households, adjustments to the national accounts or other data sources are frequently used. Here, interest is often on the fraction of income on the factors that might affect them such as, globalization, tax policy, technology, etc.. (Atkins, Bourguignin, ed., 2000)

Governments continuously make and change laws affecting the distribution of economic benefits and goods in their societies. Almost all changes, from the standard tax and industry laws to divorce laws have some distributive effect. As a result, different societies have different distributions. Every society is always faced with a choice about whether to stay with the current laws and policies or to modify them. Distributive justice theory provides guidance for these unavoidable and constant choices. For instance, advocates of the difference principle are arguing that we should change our policies and laws to raise the position of the least advantaged in society. Others are arguing for changes to bring economic benefits and burdens more in accordance with what people deserve. Libertarians usually urge a reduction in government intervention in the economy. Sometimes a number of the theories will recommend the same change in policy; other times they will conflict. Contrary to a popular misconception, economics alone cannot decide what policy changes we should make. Economics, at its best, can tell us the effects of pursuing different policies.

One of the simplest principles of distributive justice is that of strict or radical equality. The principle says that every person should have the same level of material goods and services. The principle is most commonly justified on the grounds that people are owed equal respect and that equality in material goods and services is the best way to give effect to this ideal. (Carens, 1981)

The difference principle says that the wealth of an economy is not a fixed amount from one period to the next. More wealth can be produced and indeed this has been the experience of industrialized countries over the last few centuries. The most common way of producing more wealth is to have a system where those who are more productive earn greater incomes. (Crocker, 1977)

Resource-based principles recommend equality of resources. Interestingly, resource-based principles do not normally recommend a patterned outcome — the idea being that the outcomes are determined by people's free use of their resources. Resource-theorists claim that the Difference Principle is insufficiently ‘ambition-sensitive’ and that provided people have equal resources they should live with the consequences of their choices. They argue, for instance, that people who choose to work hard to earn more income should not be required to subsidize those choosing more leisure and therefore less income. (Arneson, 1990)

The Welfare-based principles are driven by the idea that what is of primary moral importance is the level of welfare of people. Advocates of Welfare-based principles view the concerns of other theories such as equality, the least advantaged, resources, or liberty as derivative concerns. Resources, equality, or liberty are only valuable in so far as they increase welfare, so that all distributive questions should be settled according to which distribution maximizes welfare. The welfare functions proposed vary enormously both on what will count as welfare and the weighting system for that welfare. For almost any distribution of material benefits there is a welfare function whose maximization will yield that distribution. (Dick, 1975)

Most contemporary versions of the principles discussed so far allow some role for the market as a means of achieving the desired distributive pattern. The Difference Principle uses it as a means of helping the least advantaged; utilitarian principles commonly use it as a means of achieving the distributive pattern maximizing utility; desert-based principles rely on it to distribute goods according to desert, etc (Nozick, 1974). In contrast, advocates of Libertarian distributive principles rarely see the market as a means to some desired pattern, since the principles they advocate do not allegedly propose a ‘pattern’ at all, but instead describe the sorts of acquisitions or exchanges which are themselves just (Nozick, 1974). The market will be just, not as a means to some pattern, but because as the exchanges permitted in the market satisfy the conditions of just exchange described by the principles. For Libertarians, just outcomes are those arrived at by the separate just actions of individuals; a particular distributive pattern is not required for justice. Robert Nozick has advanced this version of Libertarianism (Nozick 1974), and is its most well-known contemporary advocate. (Nozick, 1974)
Throughout most of history, people were born into, and for the most part stayed in a rather firm economic position. The distribution of economic benefits and burdens was seen as fixed, either by nature or by God. It was when people realized that the distribution of economic benefits could be affected by government did distributive justice come into play.

A.B. Atkinson and F. Bourguignon, ed. (2000). Handbook of Income Distribution, v. 1. Elsevier. http://books.google.com/books?id=57nvtVnTUzIC&source=gbs_navlinks_s

Arneson, Richard, 1990, “Liberalism, Distributive Subjectivism, and Equal Opportunity for Welfare” Philosophy and Public Affairs, 19: 158-194

Carens, Joseph, 1981, Equality, Moral Incentives and the Market (Chicago: Chicago University Press)

Crocker, Lawrence, 1977, “Equality, Solidarity, and Rawls” Maximin’ Philosophy and Public Affairs, 6: 262-266

Dick, James, 1975, “How to Justify a Distribution of Earnings”, Philosophy and Public Affairs, 4: 248-72.

Edmund S. Phelps (1987): "Distributive justice," The New Palgrave: A Dictionary of Economics, v. 1, pp. 886–88.

Nozick, Robert, 1974, Anarchy, State and Utopia (New York: Basic Books)