ARE you reaching your thirties but do not feel grown up? Still unhitched and childless or wandering from one career to the next? If so, you are part of an “odyssey generation” identified by American researchers.

“There used to be four common life phases: childhood, adolescence, adulthood and old age,” David Brooks, a cultural commentator, noted last week. “Now there are at least six: childhood, adolescence, odyssey, adulthood, active retirement and old age.”

The odyssey years cover the ever-widening transition period between student life and adulthood, according to William Galston, a senior fellow at the Brookings Institution, a Washington think tank. “The word ‘odyssey’ captures the sense of exploration,” he said. “The three basic undertakings of adulthood are to get a job, to find a mate and to reproduce. There has been a massive deferral of all those commitments.”

Galston has conducted a social survey for the Hewlett Foundation, The Changing Twenties, which reveals the generational shift. In 1970 in America, only 21% of 25-year-olds were unmarried; by 2005 the figure was 60%. A majority of couples, 65%, now cohabit before tying the knot; 18% of men and 14% of women aged 25 to 29 still live at home with their parents.

Even by their thirties Americans are not sure they are fully adult: 25% of those aged 26 to 35 chose “yes and no” as the answer to the question, “Do you feel you have reached adulthood?”

Mike LaHood, 30, a digital video maker in San Francisco, said: “I don’t feel like an adult in the sense that I don’t expect kids to call me ‘Mr’. It’s odd to me when they do. I’m not ready to settle down and have a family and do all the things that I anticipate come with adulthood.”

LaHood had one serious relationship in his twenties lasting five years and tried out different jobs before finding his niche. His present career was “not something you could conceive of when I was 12 years old because the technology didn’t exist”, he said.

Galston, father of a 23-year-old, says the film Knocked Up, directed by Judd Apatow, identifies the lack of ground rules for twentysomething men. After the hero has a one-night stand with a high-achieving young woman, he asks his father for advice. “The father says, ‘I’ve been divorced three times and you’re asking me?’ At this point he [the hero] realises he has to work things out for himself.” The odyssey years do not only affect young men, even if young women are experiencing more professional success than before. Tina Neal, 31, who works in Washington, said she was not ready to settle down yet. “My parents recently said to me, ‘What’s your plan?’ but it is nearly impossible to have one for my personal life,” she said.

Diana West, author of The Death of the Grown-Up, believes that Americans are turning into “eternal adolescents” who cannot distinguish between right and wrong. “No wonder we can’t stop Islamic terrorism,” she said. “We haven’t put down our toys yet.” She believes that youth now stretches from little “baby Britneys” (Spears) to ageing “Old Micks” (Jagger).

On the plus side, West and Galston agree that the generation gap has shrunk between children and their parents, who are now closer than they were 20 years ago. “There’s a real nexus of tastes and behaviour and dress. Children expect their parents to be more like bud-dies,” said West.

Nor are they part of a drop-out generation. The odyssey years are competitive and come with new pressures of their own. “There is a lot of expectation that you can have a career that really matters and a life of success,” LaHood said. “People won’t settle for just anything. They want to be happy.”

By 35, wanderers are beginning to put down roots. “Being 15 or 35 is not so different to 20 years ago, but it is very different to be 25,” said Galston. In this, he believes the United States is following trends set in Britain and Europe: “Americans tend to think we are on the cutting edge of a social revolution, but by European standards we’re still stick-in-the-muds.”

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