For anyone who finds themselves 5-10 years away from retirement, I'd have to recommend this book.
I just listened to "The Investment Answer" by Daniel C. Goldie and Gordon S. Murray, which was recommended by a client. (Thanks, Mike!) I believe their views on how people should approach long-term investing are right on the money. (Pardon the pun!) You can read this book in one sitting, or listen to it in its entirety in just 45 minutes.