The DITA Project #10: Group topics in DITA maps
Referring to DITA maps from a book map or from another DITA map provides a great way for grouping topics. Refer to the DITA map in the bookmap whenever you want to include the collection of topics in the bookmap.
Tip: You can still use a DITA map to group topics when slight variations in the map are required (such as a topic describing how to use a feature applies to variant A of the product but not to variant B of the product.) Apply conditions to the topic references in the DITA map (such as “gram-negative”) and when the map is published (for example, for “gram-positive”), topics can be filtered out by condition.