It’s a tale as old as time. You’re in the mood, but she’s not. Or she’s in the mood and you’re . . . well, who are we kidding, you’re always in the mood.

Maybe you have moves that can occasionally change her mind, like that thing you do when you kiss her neck right there, or the way you stroke the backs of her knees just right.

But sometimes, even your A game gets you nowhere. Should you know when to fold ‘em?

We asked Amy Muise, Ph.D.—a postdoctoral fellow at the University of Toronto who researches sexuality and relationships—for tips on how to turn that “no” into a “yes, yes, God yes.”

Why her? Because her current research is all about the struggle between his-and-hers libidos, and why they don’t always line up.

This phenomenon is so common, it actually has a name: desire discrepancies.

In one of Muise’s studies, 80 percent of people had experienced a desire discrepancy with their partner in the past month.

Sometimes, she tells us, it’s just the way you’re getting started.

“A person might not like the way sex is being initiated,” Muise says. “Or she might be interested in closeness or some type of affection, but notsex. She might have had a stressful day and just needs some space.”

All of these reactions are perfectly normal and not a reflection on you or your desirability. But it becomes a problem, Muise says, when you sense that she isn’t interested but “make initiation attempts anyway—pretending not to notice (her) disinterest.”

What should you do instead? Muise recommends just talking to her. Don’t let the sex you want but aren’t getting be the pissed-off elephant in the room.

And we don’t mean pouting because your advances are refused. We mean asking questions. Something straightforward like “Is there anything I can do to get you in the mood?“

This strategy may not necessarily change her mind, Muise says, but “if she is asked the question, she may realize that spending some time relaxing, or being affectionate, might get her in the mood.”

But if she says no, Muise recommends that your next question is to ask her for a raincheck. Yes, those exact words. “Can I have a raincheck?”

It sounds silly, but it demonstrates that A) You’ve accepted that it’s not happening tonight, so she doesn’t have to keep rejecting you again and again before you get the point, and B) You’re not upset, and you’re already looking to the sex you’ll be having tomorrow or the next night.

“If a person is understanding about their partner’s need to not have sex, it is more likely that their partner will be motivated to meet their sexual needs in the future,” Muise says.

Demonstrate to her that you’re willing to wait. Do it gracefully and without judgment or pushiness, and the next time you ask, well, let’s just say that good things come to those that wait.