Rules for Productive meetings

There are numerous resources, both in print and on the net, that express ways of making meetings less onerous and more productive. Here are mine.

• Work out how many man-hours (meeting length times the number of attendees) will be consumed during the meeting. If that number exceeds the potential benefits of the meeting itself, the meeting isn't worth it.
• How do most people treat the reminders that Outlook pops up? Most click 'Snooze' until the time the meeting starts, then leave their desks. The intention is to give yourself enough time to get to the meeting on time. Make sure you and your attendees use the tool for what it was intended and be there on time. Always start the meeting promptly, and don't pander to those who arrive late by going back over what has already been stated.
• When inviting someone who has a really busy calendar with back-to-back meetings, try starting your meeting at ten minutes past the hour, giving him/her time to transition between meetings.
• AOB. This can generate sufficient unplanned conversation to push the meeting over it's scheduled finish time. Don't bother with this on the agenda, it has little purpose. If people bring up items not on the agenda, put them in a 'parking lot' instead. Record these items and discuss them 'offline' or add them to the agenda for the next meeting.
• You can persuade people to come to a lunchtime meeting by providing lunch. If your meeting is important enough, arrange for sandwiches and fruit to be brought in to the meeting room at an appropriate point.
  

Feel free to add your own 'rules' in the comments.