In a perfect world, everyone would show up to the workplace in smart, office-appropriate attire. But somewhere in a haze of zombie apocalypse t-shirts, too-tight men’s trousers, and sky-high hemlines, things went horribly awry. While it’s no fun to be the fashion police, sometimes you just have to draw the line when it comes to managing what your employees wear. And you shouldn’t be afraid to do so, says New York City-based personal and corporate brand expert Rachel Weingarten, author of Career and Corporate Cool. She offers these tips to set a dress code that works for your office.

Own it. You know the style you want your company to project. If your brand is sophisticated and stylish, but your employees are showing up in flip-flops and shorts, something’s got to change. And that’s OK.

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“You don’t have to subscribe to the belief of ‘wear whatever you want, we’re informal,’” Weingarten says. “You’re running a business. You are allowed to impose such requirements on your employees.”

Check it. Laws about employee practices vary, so check your state’s laws about what you can and can’t demand in the workplace. Your dress code should always be gender-neutral – talk about “visible underwear” instead of “bra straps,” for example – and should not demand anything that causes an issue for someone with a disability. It’s always a good idea to run these types of policies by your attorney to make sure they’re ready for prime time.

Practice what you preach. Do as I say not as I do doesn’t work for dress codes. Employees take their cues from the top and if you’re showing up in ripped cargo pants and an old concert t-shirt, your fashion demands are likely to sound hollow. Model the look you want others to emulate, Weingarten says.

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Get the word out. Weingarten advises against sending out a chiding “clothing nanny” memo that could end up as a point of ridicule on someone’s blog or web site. Tell people what you expect in your employee manual and use humor or a light touch in employee communications. Infographics can be a great way to show people what you mean, she says.

Correct, as necessary. Not everyone has the same definition of terms like “business casual” or “office appropriate,” Weingarten says. If an employee still isn’t getting it, you might need to discuss it directly. This can work best if you have a peer system in your office, so it’s not a reprimand but a suggestion from a co-worker or office pal who says, “By the way, it’s a good idea to leave the yoga pants at home. The office policy is to wear slacks or skirts.”

Make sure your policy evolves. Trends like sheer blouses and super-short skirts come and go. Weingarten says your dress policy should evolve, as well. Review it once a year to ensure it’s still reflective of your business and its image. Getting feedback from employees can also help you improve it to spot troublesome office fashion faux pas while relaxing areas where it might be overly strict. 

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