To Transform Your Meetings From Pitiful to Productive, Always Have an AgendaIt's a tool you already know about but probably never use. Maybe you should.

According to research by the online meeting company Fuze, more than $37 billion is spent each year on unproductive meetings. Let that one sink in for a moment. That's 37 billion -- yes, billion, with ab-- yet this seems to be an expense that no one is tracking or that is ever measured.

Many of my clients across the globe complain about how many meetings they're in every week, how much time is wasted and how inefficient the meetings are. Many times, they don't even know why they are in a meeting at all. The reality is, meetings are driving people crazy. Designer Karl Lagerfeld once expressed this sentiment by saying, "I don't do meetings."

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The solution to this problem is one that is very simple -- and one that everyone knows about but often doesn't use. Simply use an agenda. If you use an agenda, you can dramatically increase the effectiveness and efficiency of any meeting, no matter if it is with one person or a group.

Here are some guidelines for using an agenda:

Have one.

Every meeting that is important should have an agenda, in writing and printed out so everyone can follow along. No one would go on a business trip without having an itinerary, confirmation numbers, hotel reservations and boarding passes. An agenda is a central document for the meeting regarding what you want to cover. It provides focus and keeps everyone on track.

Agendas should have a few objectives.

Laying out two to three objectives at the top of an agenda is a great way to increase focus. What do you want to achieve in the meeting? Solve a problem? Brainstorm ideas? Make a decision about a project? You can't hit a target if you don't know what it is. As Comcast executive David Cohen once said, "Meetings with no goal, also known as 'coffee shop' meetings, can be huge time wasters if you're not efficient with them. Always know why you're meeting, and make sure it's important. Try to keep them to 30 minutes, max."

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Send it out in advance.

If you send the agenda to people who will be attending the meeting, it gives them a chance to think about what is going to be discussed and to prepare in advance. They can bring materials research, ideas and information to the meeting. Also ask everyone if they have anything they would like to add. Asking for input gets better buy-in from meeting attendees.This one point alone makes a meeting immediately much more effective. Many of the people I meet never take the time to do this because they are too busy, but ironically this simple technique can save everyone so much more time.

The person facilitating the meeting should stick to the agenda.

The person facilitating the meeting should stick to the agenda. If people try to go off topic, the facilitator should gently steer them back. When items come up that are not on the agenda, a meeting can go long or be derailed entirely. Items not on the agenda should be noted and covered at a different time. How many times have people sat in meetings while someone rambled on about something off topic? Don't let people practice off agenda-itus!

Related:Make Sure Your Meetings Don't Waste Everyone's Time by Doing These 10 Things

Agendas should have time estimates for each topic.

In an ideal world, every item on the agenda should have a time estimate. It can be slightly flexible, but this also helps the facilitator stay on track. As a professional speaker and trainer, I facilitate hundreds of live training programs every year, and I always start and finish on time. My secret weapon is -- you guessed it -- my timed agenda!

If you can have the discipline to have agendas for meetings, it can transform your organization.