Your boss, your group leader, or your direct report wants to do something that just isn't going to work. You have two options: Respond to their proposal point by point in a well-structured email, or approach them in person to explain your alternative. The first is so tempting and so much easier, but research shows that you're more likely to get your way with the second.
A new study from the University of California, Berkeley, looked at how we think about people we disagree with when we communicate about those ideas. The very short version is that we're more likely to humanize the person behind the words if we hear the idea with all the silent cues people give during in-person speech. That means your posture, your tone, and how you pause are all persuasive elements that could tip a disagreement in your favor.
The reason this works comes down to how spoken communication layers in emotional qualities. Even though some claim that feelings at the office are unprofessional, the researchers found that persuasive disagreements conducted in person made the speaker seem "more intellectual and emotionally warm than those whose opinions are written," according to a press release. The effect wasn't limited to visual interactions — phone conversations had the same outcomes. In short, speaking to your boss is more likely to remind her that you're a person too.
Of course, this doesn't mean that face-to-face conversations will automatically make your opinion come out on top. And if your supervisors asks for a write-up of your proposal or disagreement, don't back out of it because you'd be more persuasive in person. But given the choice between an email rebuttal and a chance for dialogue, try walking over to a desk or an office next time. You and your colleague might figure out a better way to proceed.