Diane Serviss. Released 1st October 2018 by Rowman & Littlefield, it's 144 pages and available in paperback and ebook formats.
The designs range from truly whimsical (see cover) to more standard fare (toques, caps, slouchy hats, etc). Each of the 30 included designs follows the same format. The introduction includes a general materials description of the required yarns along with specific model instructions and measurements. The directions are clear and understandable. I really liked that each of the projects is pictured several times from different angles! This is such a cool feature and one that other pattern books would do well to follow. Also (hallelujah!) the yarns for these projects runs the gamut from super chunky to worsted weight. The projects range in difficulty from beginner to moderately experienced; something for everyone. All of the hats seem to be sized for adults though there is one matching project sized for children.
There are many lovely projects included and at my quick search they didn't appear to be available elsewhere (ravelry, etsy, etc).
The photography is lovely and full color. The book is well edited and appealing. Just a good job all around.
Four solid stars.
Disclosure: I received an ARC at no cost from the author/publisher for review purposes