A method comprising: pre-generating insights for each of a plurality of user-content combinations, each user-content combination comprising a different respective combination one of a plurality of first users and one of a plurality of first pieces of content, wherein each insight specifies a relationship type and other content having that relationship with the respective first content; subsequently receiving a query seeking insights on a target one of the first users and first pieces of content; based on the query, identifying the respective set of insights for that user-content combination; subsequently pruning away one or more insights which specify no related pieces of content to which the target user is permitted access; and outputting at least one of the remaining subset of insights to the target user.