This paper is based upon an analysis of all marriages in England and Wales in 1976. It shows that the pattern of variation with age of age differences in marriage is not simple but is characterized by a change of direction in middle age. In particular it is apparent that both sexes are more likely to marry an older person at the age of 50 than at the age of 30. The same pattern is found in a large number of other countries. Some explanations are offered which relate to the meaning of marriage in later life. (EXCERPT)