The total number of early retirement pensiones has risen sharply since the end of the 1960s. The increase was greatest during the early 1970s following a reform in 1970 which extended the right to early retirement pension to older workers because of labour market considerations. This article discusses various conceivable explanations for the growth in the number of early retirement pensioners and regional variations of this phenomenon. The following explanatory factors are considered: (a) The prospects of getting (keeping) a job. (b) Work capacity. (c) The nature of the pension scheme. (d) Alternative possibilities of support. (e) Preferences concerning early retirement pensions. The discussion focuses on two explanations highlighted in the public debate in Sweden: changes in pension legislation and the role of the solidarity wages policy. An empirical analysis of variations at the provincial level reveals a definite correlation between the proportion of early retirement pensioners and various indices of unemployment and underemployment.