One of the best known guidelines for meetings is Robert's Rules of Order . In some formal settings like Congress or Parliament, Robert's Rules are used extensively. The Chair decides who that person will be. The speaker may speak only on the issue being considered. Those wishing to speak will be given an opportunity.
Decisions require a motion, a second and a vote.
Once voted upon, no further discussion is permitted. Set a time frame for the meeting as a whole and for specific topics on the agenda. A time limit focuses everyone's attention and adds to the clarity of the discussion. It also helps the Chair in preventing an aimless discussion. If your meetings seem to wander and drag on, consider bringing an alarm clock and put it in plain view.