Most often used to configure a set of items (for a report, a toolbar, etc) when
Users must be able to see the available pool of items, see the current set of items that exists, and have a means to add and remove items from their current set.
Alternative: "Meta Pattern"
Title, summary and context stay the same
It has to be absolutely clear to the user which items he can select from and which ones are already selected. The size of the pool of items to select from may range from only a few to large amounts of items and changing the selection might be a common or rare usecase.
Ask yourself two questions:
1. Will the selected items be displayed regularly but only rarely changed or will they only be displayed when the selection is changed?
2. How many items are usually in the pool?