The 21 Irrefutable Laws of Leadership: Follow Them and People Will Follow You (10th Anniversary Edition)

It's a great book , for all fundamentals of leadership , I used it more for a primer . But simply highlights all the the fundamentals required to be an exceptional leader in any field .
As a Military officer I would say a few more would be good .

Absolutely life changing. I have implemented many of the Laws within my business, starting with the Law of the Lid. An acronym that we use daily is PLANAHEAD, this was in The Law of Navigation chapter 4.