How do I close an event so that it does not show up in the open events list?

How do I close an event so that it does not show up in the open events list?

In Client management system users need not close an event manually. Events will be automatically closed once the End Time elapses.

For example, if the End DateTime is 09/17/2010, event will be closed automatically next day, i.e., 09/18/2010.