It’s not your grandma’s retirement anymore. Today, the journey toward total retirement as we used to know it can actually take many years; economists refer to the transition period as “bridge employment.” As more and more Americans choose, or are forced, into bridge employment, the expectation of what retirement really means is rapidly changing.

The research of Boston economist Joseph Quinn shows that, currently for many seniors, retirement is not a one-time event, but rather a process. He attributes it to a changing economic picture that encourages more seniors to choose work over leisure. Bridge jobs, Quinn says, “tend to be lower pay and less likely to have pension and health benefits, but since many people are taking these jobs voluntarily, there must be advantages to them (such as less physically demanding work; and more than half of bridge jobs are part-time). According to data from the University of Michigan’s Health and Retirement Study, about 6 out of 10 men and women of retirement age plan to continue working when they leave their full-time positions. Quinn’s data results further shows that bridge employment is highly sought after at both ends of the wage spectrum; blue-collar workers acting out of financial necessity; wealthier ones seek it as a lifestyle choice.

Are bridge jobs simply a bridge to retirement or is it just another job change, maybe one of many, in an unending work career? Older Americans are facing a gradual erosion of retirement benefits, said Monique Morrissey, an economist with Economic Policy Institute, a Washington-based think tank. Specifically, she points to the transition to 401 (k)s over defined-benefit pensions; and there’s the eventual increase in the retirement age up to 67. Wage income is becoming an increasingly important part of retirement planning for many seniors (the traditional model of a retirement income was formerly the “three-legged stool” of Social Security, savings and pensions).

But since the mid-1980s, earnings as a percentage of income has more than doubled and is still rising (for people 65 and older), from an analysis of census data by the Social Security Administration. To cover her bills, Gloria Adamson, 81, started working as an adjunct professor in the Colorado community college system 13 years ago (according to a 2014 congressional report, most adjuncts get no benefits an often earn a fraction of what tenure-track faculty make. Thus, Adamson was never able to build up much savings or contribute to her pension). She never planned to be working this late in life: “I simply have to work,” she says. “Retirement isn’t even in the picture, to tell you the truth.” (Source: “Bridge employment”-Associated Press-The (Sunday) Vindicator, April 3, 2016)