Jason Shah, CEO of Do.com, which recently launched a tool promising less-painful meetings, may have spent hundreds of hours speaking to knowledge workers about their experience with meetings, but you probably don't need more than a minute to come to the same conclusion Shah and his team eventually reached: Meetings are generally excruciating.

Between personal experience and the dozens of stories posted online each week about "fixing" meetings, it doesn't take a background in sociology (which Shah has) and a ton of market research to reveal the working world's simmering hatred of meetings. And Shah's diagnosis of the fundamental problem with office get-togethers won't come as a total shock to most.

"It's not rocket science. There are dozens of specific problems, like people show up late--there's no agenda," he told Inc.com, "but I think it's fundamentally a disrespect of people's time."

But that doesn't make all those hours listening to entrepreneurs and employees complain about meetings wasted effort on the part of the Do.com team. Talking to Shah, one can see that he has thought deeply about exactly why meetings go wrong, what that reveals about human nature and workplace dysfunction and, most important, how to fix the problems. He offered five essentials for a well-run meeting boiled down from all those conversations.

1. Does the meeting need to happen?

This bit of wisdom couldn't sound simpler, but actually putting it into practice can be tricky. Some organizations are simply meeting mad, making it difficult for individual contributors to rein in their schedules. But even if you're the boss, the lure of the full calendar can be hard to resist for subtler reasons than a displeased supervisor.

"People's worth is sometimes measured by how many meetings they have," Shah says. "When people are like 'I have to run to another meeting, sorry!' there's always this tacit feeling that that person is important." This ego boost is part of the reason people leave pointless meetings on the calendar, but your level of busyness shouldn't be an indicator of your worth.

"Be ruthless with your own calendar," Shah suggests. "Cancel meetings if you need to. Don't default to 'let's have a meeting about this.'"

2. Be very clear about the purpose.

How can you ensure you're not falling into the trap of meetings for the sake of meetings as per point one? Make sure each and every gathering on your calendar comes complete with an incredibly clear purpose. This should look like, "by the end of this meeting, this decision needs to be made," or "we're here to discuss X." Not "sales meeting," Shah advises.

Not only will having a clear agenda help keep meeting mania in check, it will also keep your time together from being hijacked by off-topic loud mouths. "Most people aren't comfortable with silence, so if there's a lull, even for five seconds, all it takes is the lowest common denominator of the person who's not comfortable with silence to say, 'Oh, we should talk about this!' And now you're shooting from the hip haphazardly," he says. A clear agenda makes that less likely.

3. Engage people beforehand.

Once you've thought hard about whether you can kill the meeting and have laid out its purpose, you're still not done with meeting preparation, Shah insists.

"Usually a person calls a meeting and the most engagement they have with everyone else is that they send a calendar invite around," he says. That's not enough. "If I'm calling the meeting, I should list out a few key questions for people to think about." Recall Amazon boss Jeff Bezos's habit of insisting executives write out a complete multipage memo of their thoughts before meetings. You needn't go that far, but you should give all participants a bit of mental homework before you get together.

Laying out what you want from people "is a seed in somebody's head," Shah explains. Plant it, and when participants are going about their day, waiting for the bus or walking around, at least part of their brains may be chewing on the problem you hope to resolve, giving them time to get inspired or mature their thinking--and making the eventual meeting more productive.

4. Actually start on time.

This is another essential that appears simpler on the surface than it actually is. Punctuality isn't just a matter of politeness or avoiding the ripple effect of making folks late for subsequent meetings. It's also essential for engagement and rapport-building.

Imagine three people are on time and one is late for a meeting. The prompt attendees will naturally engage in a little banter while they wait, building rapport. When the fourth person eventually walks in the door, he or she will be missing that context and the conversation will be lopsided from the start. Or worse, the original on-time three will actually get down to business before the latecomer arrives. Someone will have to catch the tardy colleague up, boring the other two to tears or offering them an excuse to start checking email, etc.

If that happens, "I've lost them," Shah says, likening a meeting to a performance or movie. "If a movie loses someone, you're not going to get them back. I don't care how many buildings you explode."

5. Document and share the main points.

"Meetings are still this black hole of information," according to Shah. "All this stuff happens and sometimes participants--but even more so the people in the organization--don't know what's going on." The problem of disseminating information about what was decided in meetings isn't just that next week's get-together is likely to be redundant, but also that this lack of clarity will lead to lack of accountability. Feeling like the information and to-dos generated never fully make it out of the meeting room "is discouraging over time," Shah says.

People end up feeling as though they're going to the same meeting every week and disengage. Less-than-punctilious employees use the confusion as an excuse to slack off, further annoying everyone.

Have you found any other essentials for a truly productive meeting?