What goes on in a man'/women's mind
How important is sex
What your husband/wife wants you to know
Both books are short and easy to read. This was key for us because Russty has a short attention span when it comes to books. I would definitely recommend reading this as a couple, but if your spouse isn't game, just read the one meant for you. You'll learn a lot about the person you're married to. Do you have any marriage books that have helped you?