Retirement is the withdrawal from one's position or occupation or from one's active working life. A person may also semi-retire by reducing work hours or workload.

Many people choose to retire when they are elderly or incapable of doing their job due to health reasons. People may also retire when they are eligible for private or public pension benefits, although some are forced to retire when bodily conditions no longer allow the person to work any longer (by illness or accident) or as a result of legislation concerning their positions. In most countries, the idea of retirement is of recent origin, being introduced during the late-nineteenth and early-twentieth centuries. Previously, low life expectancy, lack of social security and the absence of pension arrangements meant that most workers continued to work until their death. Germany was the first country to introduce retirement benefits in 1889.

Nowadays, most developed countries have systems to provide pensions on retirement in old age, funded by employers or the state. In many poorer countries, there is no support for the elderly beyond that provided through the family. Today, retirement with a pension is considered a right of the worker in many societies; hard ideological, social, cultural and political battles have been fought over whether this is a right. In many Western countries, this is a right embodied in national constitutions.

An increasing number of individuals are choosing to put off this point of total retirement, by selecting to exist in the emerging state of pre-tirement.