Good question. I have my Christmas ones grouped together, baby/children together. I have my fabric dying together. The books that are sampler type or a variety of blocks are all together...just kind of general. Then my brain kind of groups others together like the old Leisure Arts books as well as kinds like the Brandywine Designs types. They are in a cabinet...and who cares if I have to go through and look at the spines or covers of many books to find the right one. I love doing that. Important thing, I think, is to keep the books with the obvious themes grouped together...obvious themes being christmas, baby/kids, etc. Works well for me. If I am in a hurry and want to make sure a book is in the cabinet, I lay it flat until I get a chance to put it where I want it. Mostly it is up in my brain where I want things. I am a slob about most things house work wise but I like to have my books organized and my fabric folded!