Spaces introduce the concept of homepages. These pages collect the most important documents of a given type.

There are use cases where you do not want to store documents of some types in your space. Typically you do not need to define resource types or topic types, experience levels or module types for each space separately. Instead you define these types for a couple of spaces and add them to a designated space. This space is set as the delegate space for all spaces of this group.

You may define more than one delegate space per space. If you send a page to its homepage, the list of delegate spaces will be consulted if the default homepage for that doctype does not exist. Each space on that list is checked for providing that homepage. The first that matches that requirement will store the document.

Delegate spaces help to organize information that is used by more than one space.

A space may define zero or more spaces that will be taken into account on projectdoc queries (e.g. Display Table Macro). So if you separated information into different spaces you may still define the default search to include a defined set of spaces to contribute to the result set.

The list of spaces to consult is set as a space property named search-space Search Space.

For small groups of spaces the delegate spaces usually are also part of the set of search spaces. But these to closures do not necessarily contain the same members.