Elizabeth Bear and Sarah Monette, with a degree of apparent effortlessness that is astonishing, have pulled off not one but several very difficult things in A Companion to Wolves.
The first, and by no means the least, is the sometimes vexed collaboration issue. I have read co-authored books in which I could have chopped out and parceled into neat little piles the bits that belonged to the various authors because the voices simply never gelled enough to produce perfect seamlessness. Here, it just doesn’t even matter. It flows. The two authors work as one; it’s not so much cooperation as a symbiosis. A job very well done.
The second is the worldbuilding….The storyline is gripping… the writing is exquisite, and the book is destined to be a classic of its kind.