I have recently completed one of the great ancient books - The Book of Five Rings by Miyamoto Musashi. And thought that the book consists of ground rules that can be followed in any aspect of your life - career, personal etc.
Book of Ground: Getting to know the groundwork is really important. Build your knowledge to lead
Book of Water: Water is clear and water gets the shape of its receptacle. You should be clear and be like water always.
Book of Fire: The enthusiasm should be like fire always.
Book of Wind: The strategy is to know what other schools are doing, studying old-traditions, traditions of the world.
Book of Void: There is no start no ending. When you appreciate the nature and observe the things that are happening around you, you will naturally strike the opponent using those forces.