Hi, Owen-- Sorry for the delay in my reply, but I finally had a quiet moment to really look at this! Although our AuthDisplayHierarchy syspref is set to "Display" (with Koha 17.11.07), our authorities displays don't look like this, but I like it! I think having the trees automatically display open is best, with the click/select on a heading executing a search. We have a very complex (and messy) authority file that I'm cleaning up, so I've been looking at our authorities & their relationships a lot, and I think that as long as a user gets to see at least one broad and/or narrow and/or related term, they can click/select around to get to a desired heading. I think it's less desirable to click/select to expand or collapse the hierarchy--I think that the click/select action should execute the search & the user can then navigate to the desired heading that way & then eventually click/select the biblios. If you have an example of a related term (rather than a broader/narrower relationship), I'd find that interesting to see. Hope this is helpful! Cheerio, h2 ~~~~~~~~~~~~~~ Heather Hernandez Technical Services Librarian San Francisco Maritime National Historical Park Research Center 2 Marina Blvd., Bldg. E, 3rd floor, San Francisco, CA 94123-1284 415-561-7032, heather_hernandez@nps.gov Library catalog: http://keys.bywatersolutions.com/