Great reads posted. I would also add:
From Battlefield to Boardroom - Dennis Laurie
The Marine Corps Way - Santamaria
The Undercover Economist - Harford
The Five Dysfunctions of a Team - Lencioni
The Five Dysfunctions of a CEO - Lencioni
The Box (for anyone in the transportation industry)
Talent Masters
Atlas Shrugged
A Sense of Urgency - Kotter
Emotional Intelligence
Blink - Gladwell (also The Tipping Point, Outliers, What the Dog Saw)
Built to Last & Good to Great - Collins
Driving Change
The Dip - Godin
Guns, Germs & Steel
The Informant!
All The Devils Are Here - Nocera
The Alchemist - Coelho
Man's Search for Meaning
Between a Rock and a Hard Place
The Essential 55
Math Magic
The Number Devil
The last bunch of books may not appear to be business-related at face value, but look again - there is intrinsic value in lessons that apply to businesses and business people both. (The last one, Math Magic, admittedly is more useful before the GMAT
Mick