If you're reading a book about an idea or issue, bring in a person who can add a blast of inside knowledge to the discussion. For example, if you're reading Monkey Mind, Daniel Smith's memoir about anxiety, bringing in a meditation teacher to try some of the techniques Smith suggests can add a new layer literary understanding, as well a bonus hit of group-wide calm. This idea can work for fiction too. Say you're reading the lyrical, brilliant In the Shadow of the Banyan Tree, by Vaddey Ratner. A historian's comments about what happened in Cambodia during the Khmer Rouge can help everyone better understand the very true true facts behind the fiction.