In Serendipity, my father H.D. Johns reflects on his "system of thinking" about people, relationships, and life through forty years experience as a psychotherapist.
John Gottman poured 40 years of research and insight, for what makes good marriages 'good', into 'The Seven Principles'. It's like an owner's manual for your relationship.
Dan Wile's final book published posthumously with help from his wife, therapist Dorothy Kaufmann. The definitive resource for understanding Collaborative Couple Therapy. (Only available at Amazon.com)