At my last engagement they actually put out a memo called “Meeting Etiquette.” It was an attempt to get everyone’s out-of-control calendar(s) under control. The items were:
-No meetings before 9AM or after 4PM
-No meetings longer than an hour
-All meetings must start on time and should end no later than 5 minutes before the official end (to give attendees time to get to their next meeting)
-No meetings over lunch (12-1PM); any meeting during this time MUST provide food
-Every meeting should have an agenda/talking points published PRIOR to the start; if there is no agenda published attendees have the option to not attend.
It sounds like simple stuff but there was definitely a positive effect; considering studies have shown humans average about 47 minutes of concentrated attention before their minds wander unintentionally the 60 minute cap helped.
I personally try to never schedule a meeting longer than 30 minutes; meetings are like “work” in the sense that they expand to fill the space provided…I’m the king of taking meetings in inappropriate directions so the timebox keeps me out of HR :).
As for bad meetings…I usually politely say that we are not getting value in the session, should we take a minute to recenter or reconvene at a later time. Those are on my good days. On my bad days I have been known to excuse myself with “I have to return some videotapes.”