Karen Simons was out of the professional world for more than 20 years to raise her three children. Now she's a financial planner at the investment advisory firm Yeske Buie.

She made that change happen through a "returnship," the grown-up version of a college internship that companies are increasingly offering to professionals who've taken a break from the labor force.

"I never thought I would have an opportunity to explore an entirely new career," said Simons, 60.

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Goldman Sachs offered one of the first returnship programs, in 2008. More recently, Apple, Ford and Johnson & Johnson have launched programs, and Procter & Gamble has just announced they will be offering returnships.

In the last year or so, the reentry positions, which are paid and typically last between six weeks to six months, are growing among financial advisory firms. Northwestern Mutual, TD Ameritrade and Vanguard now offer them.

Firms must get creative in recruiting employees amid record low unemployment, and returnships provide a particularly good way to bring in women, who are largely underrepresented in the financial sector, experts say.