Pulling off the ultimate career makeover

June 21, 2011, 9:00 AM UTC

If you lived in Birmingham, Ala., and wanted to rent a movie on a Friday night back in 2002, the

odds were pretty good you’d be paying David Kahn for the privilege. Back then, Kahn, 49, was the effervescent owner of 45 Blockbuster franchises in Alabama and Mississippi; by his estimate, his group of stores made up the seventh-largest video-rental chain in America, and were worth more than $15 million.

Then a little company named Netflix (NFLX) came up with a new and disruptive business model for renting videos, and soon it would harness the technology behind delivering movies over the web. Kahn was about to be Blockbusted. He was in jeopardy of losing his financial security, his self-respect, his professional life. He would have to reinvent himself — or the world would do it for him.

Feel a chill of recognition while reading this story? Thought so. In this “Age of Disruption,” Kahn’s story is hardly unique. If you haven’t actually been Blockbusted yet, you’ve doubtless lost sleep over what you’ll do if/when it finally happens.

We live and work in a time when technology has made it easier for new companies to be born. That’s the good news. The bad news is that increase in productivity has fueled multiple rounds of job cutting. Add to that the lingering wreckage of the financial crisis and the fits-and-starts recovery, and it’s clear that job change is the only constant.

Job creation is at its lowest point since 1980, while job destruction continues to rise. A full 12.6% of the workforce lost their jobs in the past recession, according to the Bureau of Labor Statistics’ Displaced Worker Survey. That’s the highest rate since at least 1981.

What all these data points make crystal clear is that the very nature of jobs in America has changed. Pensions? An ancient relic. Steady progression up the corporate ladder? Yeah, right. We’re living in a project-based economy, one moving from full-time employment with benefits to part-time employment with project-based assignments.

See also: The rules of career reinvention

Here’s proof: By the end of 2010, the number of people working part-time because they couldn’t find full-time work had nearly quadrupled since the 1950s, to 2.38 million people. “It’s a spot auction market,” says Robert Reich, former secretary of labor under Clinton and the chancellor’s professor of public policy at the University of California at Berkeley. “What you’re paid is what you’re worth at that particular time.”

That means you will change your professional identity frequently — maybe even as often as you spruce up the look of your living room. The youngest baby boomers (those born from 1957 to 1964) held an average of 11 jobs from ages 18 to 44, according to the Bureau of Labor Statistics. The Denali Group, a procurement-services company, predicts that Generation Y will have 15 to 25 jobs in their lifetime. “This can be a very exciting world,” Reich says. “In many ways, it’s much better than the old world that was more seniority-based, where you tended to work on the same thing for many years.”

Exciting if you’re in your early twenties. But not so much, Reich adds, if you’re an expert in your field, if college tuition is looming, if you aren’t as able to relocate as you once were. There’s just one way to achieve true job security: stand ready to reinvent yourself — no matter what your age, your education, your skill set, or the color of your collar — sometimes more than once.

But how?

To find out, we scoured the country to find people who have been disrupted but have managed to create a new career story. Those profiled here have successfully reinvented themselves — not because they wanted to, but because they had to. They are not 25-year-old techies; they are established professionals who were happy doing what they were doing — until they weren’t doing it anymore.

The reason some people have become successful reinventors is more about attitude than experience: One thing they all have in common is that they love learning by doing. They have come to embrace the future, using new technologies, particularly social media, to help them leverage their own professional skills. And they are not victims. At a time when many people react passively to career bumps, our reinventors took control. Read on for 5 career makeover success stories

This article is from the July 4, 2011 issue of Fortune. A shorter version of this piece appeared earlier in June.

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