A policy collection is an entity in LUSID that can contain one or more policies or nested policy collections - essentially “groups of policies”. Policy collections can be used as logical groupings for maintaining large numbers of policies. As policy collections can contain nested policy collections they may be considered a tree where the leaf nodes are all individual policies.
Policy collections, like policies, can be attached one or more Roles directly, which is the equivalent of individually attaching each of the policies in the entire tree of the policy collection.
Policy collections can have policies or other policy collections added to them either at creation, or subsequently.