“This meeting could’ve been an email.”

It’s a thought you’ve probably had before. While effective meetings can support employee engagement, alignment and decision-making, people are often roped into meetings that feel unnecessary. That can eat into precious time to get work done.

Ideally for a meeting, “a decision needs to be reached that couldn’t be reached without having all those people together,” says Laura Vanderkam, author of several books on time management and productivity. Instead, for many, “all the reason that the meeting is happening is because it’s Thursday at 10 a.m.”

Everyone should know going into a meeting why it’s necessary, what it should achieve and what the agenda is, Vanderkam says. But too often it’s unclear why a meeting is happening, or what objectives it should achieve.

Making one small swap to the agenda can help you have more effective meetings and curb unnecessary ones, according to Steven Rogelberg, Chancellor’s Professor at UNC Charlotte teaching organizational science, management and psychology and author of two books on meeting science.