These are the 27 books EVERYONE needs to read:

Self-Development

1. Willpower Doesn’t Work
2. The Motivation Myth
3. Man’s Search For Meaning
4. The Power of Positive Thinking
5. The 7 Habits of Highly Effective People
6. The Happiness Equation
7. As A Man Thinketh  
8. 12 Rules For Life  
9. The Book of Mistakes

Sales

1. To Sell is Human
2. High-Profit Prospecting
3. New Sales. Simplified.
4. The Only Sales Guide You Will Ever Need
5. Sales EQ
6. The Challenger Customer
7. Sales Management. Simplified.  
8. Same-Side Selling
9. Exactly What To Say

Leadership

1. The Outward Mindset
2. The Go-Giver
3. Brave Leadership
4. The Advantage
5. Emotional Intelligence
6. Give and Take
7. The Speed of Trust  
8. 21 Laws of Leadership  
9. Leadership and Self-Deception