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The success of your next meeting depends on who you invite. This is what you should consider.
1) Invite only people who can contribute to the meeting. Spectators bog down the process.
2) Avoid filling the meeting with allies as a show of force. This intimidates your “opponent”, which can result in counterattacks, retaliation, or false cooperation.
3) Avoid inviting people because they would be offended if they were left out. A meeting is a business activity, not a party. You can always ask the person to choose between watching others work in a meeting or letting them work on tasks that contribute to raises and promotions.
4) Be sure to invite the stakeholder (the person the problem belongs to). This person is a valuable resource for finding solutions.
5) Make sure opponents of the issues attend your meetings. They can help you find equitable solutions that they will support. Without them, any results you develop are likely to be useless.
6) Invite key participants with minor roles only to the part of the meeting where they can contribute. Schedule these agenda items at the beginning of the meeting or when you resume after a break.
7) Inviting viewers for good reasons. For example, you can invite a new employee to learn about a problem; you can include members of other organizations to gain empathy for their needs, you can invite a stranger to catalyze creative thinking.
8) In general, meetings that are held to make plans, find solutions, or reach agreements work best when eight to twelve people attend.
9) Any number of people can attend parties, social gatherings, conferences or demonstrations.
Note: Learn more about effective meetings at: http://www.squidoo.com/OneGreatMeeting/