Editor's note: This story was updated on August 2, 2017.
Inviting the wrong number of people to a meeting is sure to derail it. Writing for the Wall Street Journal, Sue Shellenbarger breaks down the number of people you should include depending on your purpose.
To consider a problem, invite 4-6 people
For problem-solving meetings, you need the minimum number of people who bring the expertise needed for the task at hand, Shellenbarger writes. Otherwise, the conversation gets off track and not everyone will be heard, warns Workfront CEO Alex Shootman.
Shootman also recommends giving each attendee a specific role. Some will provide and collect information for their teams, some will offer general wisdom, and others will be part of making the final decision. Extra attendees wouldn't have a meaningful purpose, she says.
To make a decision, invite 4-7 people
Inviting too many people is a sure way not to decide anything. Michael Mankins, a San Francisco-based partner with Bain & Co., uses what he calls the "Rule of Seven" to protect the small attendee list. According to Mankins, the likelihood of arriving at a good decision decreases 10% for every meeting participant over seven.
"By the time you get 17 people, the chances of your actually making a decision are zero," he says.
To set an agenda, invite 5-15 people
The size of a meeting for setting an agenda will vary based on the size of an organization, but should only include the people whose work or responsibilities are actually relevant to the day's agenda, according to Paul Donehue, president of Paul Charles & Associates.
To brainstorm, invite 10-20 people
Brainstorming requires a mix of diverse perspectives, so bumping up the attendee list makes more sense in this situation. Al Pittampalli, author of Read This Before Our Next Meeting, suggests you begin with 10 people—and then add in a few more people. The exception to the rule: If you can't find anyone who will truly bring a different perspective, there's no need to go beyond the initial 10 people.
To encourage people to be open with their ideas, Andrew Carton, assistant professor of management at the University of Pennsylvania's Wharton School, suggests letting participants submit anonymous ideas before the meeting (Shellenbarger, Wall Street Journal, 12/20).
How to have an engaging meeting
There are about 11 million formal meetings in the United States every day—and more than half of them may be unproductive. Why? Because many meetings are inefficiently run. They don't set or achieve clear goals. And we hold them out of habit.
Drawing on best practices—as well as lessons from across our own organization—we've created this useful infographic to guide if you really need a meeting (and if so, how to maximize everyone's time).