It’s no secret: most meetings are terrible. As a behavioral scientist and two founders of a startup devoted to improving meetings, that’s the easy part of our pitch. But fixing them? Not so easy.

We’ve surveyed employees across industries and roles, we’ve read books and articles, we’ve looked at countless tools and techniques, and we’ve learned two things: First, many experts seem to think that the key ingredient of a good meeting is its agenda. It’s hard to find a book on meetings that doesn’t start with the importance of agendas, and most of the product managers we’ve talked to have indicated that they believed agendas were central to holding better meetings. And second, there is a wide body of research that suggests agendas alone are not enough to run effective meetings.

Indeed, while you might assume that detailed agendas improve your meetings, they may have exactly the opposite effect. This is because many employees unwittingly engage in a practice we call agenda theater: They sink time and effort into agendas that create the appearance of effective meetings, without actually improving how meetings are run. What drives this counterproductive behavior — and what should meeting-leaders do instead?