Tech companies have tried everything to boost the low numbers of women in their ranks. Massive grants aimed at high-tech scholarships for girls and students of color. Longer parental leave perks for new moms and dads. Even benefits that pay for women who want to delay childbearing to freeze their eggs.

Now a growing number of both large and small tech companies are borrowing an idea from Wall Street banks: The "returnship," which brings in mid-career women (and men) who've taken time out of the workplace to care for family, offering them a path back to the office.

On Tuesday, a nonprofit called Path Forward announced that six San Francisco-based tech companies, including domain registrar GoDaddy, customer service software maker Zendesk and grocery delivery outfit Instacart, will offer 18-week internships for about 20 mid-career professionals starting in October.

While the program is open to men who have spent at least two years out of the workplace as a caregiver, it is expected to be filled largely by women. It is aimed at helping interns confront the stigma they face about time away. Also tech companies get a chance to improve their reputation as places that too many women leave. "If you're wanting more women at the senior level, this is a way to jump-start that," said Tami Forman, the executive director of Path Forward.

Forman said there's been enough interest from other companies that she plans to start two to three more groups of these untraditional interns (who, yes, are paid) in several cities early next year, each with six to 10 tech companies. The nonprofit was spun out of the New York-based email software firm Return Path, which started its own mid-career internship program last year -- Forman is a former marketing vice president there -- and now helps bring that program, which includes training and networking opportunities for the group of interns to other tech companies.

Path Forward's announcement follows another recent effort by seven technology and engineering companies -- including IBM, Intel and General Motors -- to run internships designed for women who've taken time away. The programs at these companies began this year and are part of an effort launched by the Society for Women Engineers and iRelaunch, a "career reentry firm" that runs a conference on returning to work sponsored by finance companies that have similar programs, such as Morgan Stanley, JPMorgan and Goldman Sachs. The latter firm kicked off the trend back in 2008 and even trademarked the phrase "returnship."

Carol Fishman Cohen, iReLaunch's CEO, said her conference acts as something of a recruiting hub for those existing programs, and "it occurred to us we should take the concept to another sector." She approached the Society of Women Engineers to establish a task force last year that would try and "replicate what we saw in financial services."

In tech, she says, "there’s a lack of women at every level of the organization and they’re looking for more ways to hire more of them and fill that pipeline." Cohen said men are eligible to apply, but most applicants for the established programs have tended to be women in their 40s or even 50s who've left the workforce to be a caregiver. 

Some tech companies have long offered flexible leave policies or extended sabbaticals that help their own employees return after a break. But these newer mid-career internships, says Laura Sherbin, director of research for the think tank Center for Talent Innovation (CTI), offer certain advantages. For one, it exposes employers to outside talent. And in an industry like tech, where the pace of change is faster and more disruptive than in others, the low-risk bet on hiring an intern for 12 or 18 weeks can help erase the bias many managers have about people whose resumes have glaring holes on them.

"There's a huge stigma to time off in the tech industry," Sherbin said. "There's a perception that tech passes us by even on a maternity leave, and if you've had time out of the workforce you're hugely behind. Tie that in with the bias you do see about tech workers who have a little bit of gray hair," and it's and industry particularly primed for managers who might look past candidates -- even skilled ones -- who have been out of the workforce.

Steven Aldrich, chief product officer of GoDaddy, said that's one thing that attracted his company to the idea. "The company has a chance to try the employee, in a way, and see their fit with the company, and it's a win for the working parent coming back into the workforce to come in and get experience," he said. "Those things are really challenging [when someone] comes straight back in." 

The tech industry is also trying to plug an especially leaky pipeline. According to 2008 data from the CTI, 52 percent of women with experience in the science, engineering or tech fields chose to leave their fields over time. Another 2013 study, meanwhile, compared women in multiple professions and found that after the first 12 years of their careers, 50 percent of women in science, engineering and tech were working in other occupations, while only about 20 percent of the other women switched industries over their entire careers.

Running internships for returning parents could also help send a message to younger workers. With these programs, Cohen says, "what companies are signaling to their youngest employees and the people in their 20s is that they understand that employees may take a career break -- and we want to welcome you back." 

If hiring rates are any test, such "returnships" appear successful. At Goldman Sachs, almost half of the 150 people who have gone through its program since 2008 were hired for full-time jobs; Cohen says that hire rates tend to be between 50 and 90 percent in established programs, and at the high end of that range for the tech firms so far. A spokeswoman for PayPal, which ran a program for nine interns in the U.S. called "Recharge," with the help of Forman's group earlier this year, said that seven of the nine were offered jobs.

And all six of the "Tech Re-Entry" interns working in analytics at IBM this spring, who had been out of the workforce for anywhere from two to 10 years, were recommended for full-time employment. Five have accepted jobs and the sixth is currently in final interviews at the technology giant.

"We're increasingly looking for creative ways to bring women back to the workforce who we know are incredibly competitive," said Lindsay-Rae McIntyre, IBM's chief diversity officer. She said the company is looking to expand the program.

Still, while success rates for participants tend to be high, the effect such programs will have on moving the needle -- either for the number of mid-career women in tech or the number of parents wanting to get back to work after child rearing -- could be limited. For one, the programs tend to be relatively small. Several of the pilot programs included internships for just a handful of people -- GoDaddy is hiring three interns, and there were nine in the first group at PayPal -- and iRelaunch's Cohen says existing programs tend to number 20 or 30 interns a year.

Meanwhile, the programs are largely limited to fields where job demand is already strong, such as tech and finance, and do little to help those trying to get back to work in struggling industries or those with an abundant supply of workers looking for jobs. Forman said she's heard of an effort to do a "returnship"-style program in the advertising field, but it didn't take off. "The problem with that industry and industries like it is there's 10 people lined up for every job," she said.

And in those industries where they could help bring in a few more women, warns CTI's Sherbin, hiring them only goes so far. Even programs that hire every mid-career intern they bring in won't make much progress on diversity if they don't also work to improve "bro" cultures that are hostile or toxic to anyone who's different.

"You may get them in," she says, "but they’re going to be very very short hires. Diversity for the sake of having butts in seats doesn’t do us all that much good." 

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