Nonviolent Communication: A Language of Life by Marshall B. Rosenberg
Influence: The Psychology of Persuasion by Robert B. Cialdini
Emotional Intelligence: Why It Can Matter More Than IQ by Daniel Goleman
Crucial Conversations: Tools for Talking When Stakes Are High by Kerry Patterson, Joseph Grenny, Ron McMillan, and Al Switzler
Quiet: The Power of Introverts in a World That Can't Stop Talking by Susan Cain
The 7 Habits of Highly Effective People by Stephen R. Covey