The Hole in our Gospel by Richard Stearns. Let me just say that the first chapter made me cry like a baby. Needless to say, the book is good. Think Orange by Reggie Joiner. If you are a church leader, you need to read this book. Period.
The Principle of the Path by Andy Stanley. Required if you are currently breathing.
How the Mighty Fall by Jim Collins. Reading this book for a second time.
Too Small to Ignore by Wess Stafford. President of Compassion International.