Oh, doomsday. I loves ya. I read this expecting to learn something about the different types of doomsdays that could occur, and it was very close to what I expected. The author's rating system for how likely an event is to take place is a little wonky, but his narrative is straightforward and interesting. Not much referencing to hard science studies, but enough to keep my interest. A few scenarios hadn't been on my radar, so this was good for my love of apocalypse -- a few new areas to look into for fiction reading. I'd like to see an updated edition because this was published in the mid-2000s, so some recent events and climate occurrences certainly aren't addressed. Overall definitely recommended for those whose leisure reading interests are in this area. A quick read and entertainingly written.