Approach (Theory) 
Idealized Design: How to Solve Tomorrow’s Crisis…Today, Ackoff, Magidson, Herbert
Motivational Interviewing: Helping People Change 3rd Edition, Miller
The Art of Solution Focused Therapy, Connie, Metcalf

Boundaries 
Boundaries in Relationships, Whitfield
No More Mr. Nice Guy: A Proven Plan for Getting What You Want in Love, Sex, and Life, Glover

Optimization/ Performance