The starting point of meeting effectiveness is clarity of purpose. What is the reason for the meeting in the first place? Think it through in advance and ask why the meeting is being held at all. Guard against the tendency of slipping into the habit of holding meetings just for the sake of them.
There are some questions that you can ask to clarify the purpose of the meeting.
First, is the meeting necessary? Is there some other way that you can accomplish the objective? Is there another way to hold this meeting or to solve this problem? If your purpose is information sharing, can you pass information on by phone, e-mail, or through a website?
Remember, if it is not necessary to meet, it is ...