The ability to retire is a relatively recent luxury. Only in the last forty years have most Americans considered retirement an economic right earned from a lifetime of work. Yet almost no one has considered how much of our adult lives should be devoted to work versus retirement and whether that ratio should change as the length of adult life itself changes. This paper addresses this question first by summarizing how the retired life has lengthened over time. It then describes the present situation and speculates on what may happen in the future.