What could be wrong with flexible working? Allowing team members some wiggle room when it comes to when and where they work has been shown to help attract and retain top talent, and being flexible is often touted as a great way to keep female employees, in particular, happy (though, as my colleague Jeff Haden has pointed out, people of both genders are generally equally keen on controlling their work schedules). It can even save you money.

But while the case for flexibility seems pretty open and shut at this stage, that doesn't mean that you can't get it wrong. Two new studies show that, badly executed, giving your team options can actually backfire.

Leadership buy-in is key

The first comes from "When Women Thrive, Businesses Thrive," a new study from research firm Mercer. For the study, researchers crunched through data on 1.7 million employees in 28 countries to determine not what, on paper, looks like it should improve diversity, but what policies actually make a dent in helping women get ahead. They found that some old standbys for supporting diversity really aren't all they're cracked up to be.

Specifically, if you want your flex work program to help talented women at your firm advance, you really, really need to get senior leadership involved in the effort. "Mercer's research shows that the active involvement of senior leaders in gender diversity leads to greater, accelerated representation of women in executive roles," the research release explains.

Meanwhile, common policies, like "those intended to ensure equity through flexible work schedules and leave programs ... are, in the absence of management, associated with slower improvement in the number of women in leadership positions."

Flex work as poisoned chalice

Put simply, if you change your flex work policies without getting senior leaders actively involved, you may end up hurting the prospects of female employees rather than helping them. Why might this be so? Another study published in Academy of Management Journal and highlighted in a recent Time article suggests a reason.

"The academic study found that managers often interpret a person's use of flex work options as a signal of high or low job commitment," Nanette Fondas writes. "Specifically, the research found that if a boss attributes an employee's need for flex to personal-life reasons like child care, as opposed to job performance enhancement reasons like acquiring new skills, the boss tends to assess the employee as less committed and less deserving of career rewards such as raises and promotions."

Offer flex work to your team without getting all the bosses on board, with the idea that actually using it is a sign of healthy dedication to long-term motivation and productivity, and you risk offering your team a poisoned chalice. Your flex work options sound appealing, but when employees actually exercise them, they end up penalized for that decision.

The takeaway? Just instituting on paper some flexibility for your team is far from enough. Unless you make sure your managers aren't harboring bias against those who take the company up on the offer, your policy change will probably do more harm than good.

Is the entirety of the leadership at your organization really on board when it comes to flex work?