“What happens if I think Emily is great and I want to keep her so I give her the precious telecommute she asks for, but Anna isn’t so great, so I don’t want to accommodate her schedule?” is a similar boss concern.

Valerie Jarrett says that’s exactly what she found when she was running Habitat. “My first thought is being fair,” she says. “If you’re creating an exception for somebody, then first you have to figure out what you’re going to do if everybody wants that same exception, and would it work system-wide or can you justify the distinction.”

Michael Nannes is the managing partner of the powerhouse law firm Dickstein Shapiro in Washington, D. C. He’s also a demigod for in-the-know female lawyers, because he’s created a firm that embraces flexibility and the goal of giving lawyers lives. He realized when he had children of his own that having time to be there for them was important, so he’s more than happy to accommodate other people’s different schedules. He has one lawyer who takes all summer off to coach her child’s swim team. “If you get your work done, that’s what counts.”

But even he says there are times when the policy can be awk­ward. “You get problem cases where somebody who’s not doing that well goes and opts for a part-time situation. As an employer, you do bang your head on that one,” says Michael Nannes.

Still, in Nannes’s experience, the alternative schedule discus­sion can have the benefit of prompting a useful conversation about the employee’s overall performance. “On a couple of occa­sions that’s precipitated an honest discussion about the person’s career track,” says Nannes.

Our take? You might not be able to say this out loud, but the Anna-isn’t-so-great issue is a red herring. It needs to be dealt with as a performance issue not as a flexibility issue. Make your pitch based on your top performance, and you’ll be the one to get the good deal.