For Couples Only: Eyeopening Insights about How the Opposite Sex Thinks

For Men Only, Revised and Updated Edition: A Straightforward Guide to the Inner Lives of Women

For Women Only, Revised and Updated Edition: What You Need to Know About the Inner Lives of Men

For Women Only, For Men Only, and For Couples Only Participant's Guide: Three-in-One Relationship Study Resource

The Surprising Secrets of Highly Happy Marriages: The Little Things That Make a Big Difference

For Women Only, For Men Only, and For Couples Only Video Study Pack: Three-in-One Relationship Study Resource with Companion DVD

For Young Women Only: What You Need to Know About How Guys Think

Through a Man's Eyes: Helping Women Understand the Visual Nature of Men

The Kindness Challenge: Thirty Days to Improve Any Relationship

For Parents Only: Getting Inside the Head of Your Kid

For Men Only (Revised and Updated Edition): A Straightforward Guide to the Inner Lives of Women