There is documented guidance for Microsoft® Office SharePoint® Server 2007 regarding the maximum size of lists and list containers. For typical customer scenarios in which the standard Office SharePoint Server 2007 browser-based user interface is used, the recommendation is that a single list should not have more than 2,000 items per list container. A container in this case means the root of the list, as well as any folders in the list — a folder is a container because other list items are stored within it. A folder can contain items from the list as well as other folders, and each subfolder can contain more of each, and so on. For example, that means that you could have a list with 1,990 items in the root of the site, 10 folders that each contain 2,000 items, and so on. The maximum number of items supported in a list with recursive folders is 5 million items.