The Untethered Soul - Very important book that helped Justin recognize why detaching happiness from the company success was so important.

Leadership and Self-Deception - There are two ways to treat other people: like people (with empathy), or like an objects (without empathy). If you treat people like objects who are there to achieve metrics, you will end up lying to yourself about your own role in their successes and failures and ignoring your own contributions, which is just poor management.