I have an attraction to leadership books which describe real leaders, rather than those with a polished, corporate facade. I fully acknowledge we can learn from books touting secrets and methods, but I find much more encouragement in those which help me lead in and through my weaknesses.
An all time favorite of mine is Leading with a Limp by Dan Allender, which I have spoken about multiple times on this site.
A new addition to these ranks is a book I am currently reading. The Way of the Dragon, the Way of the Lamb by Jamin Goggin and Kyle Strobel is study of leadership in weakness.
Coupled with their musings, they interview multiple humble giants of the faith. The authors spent time with J.I. Packer of Knowing God fame, Eugene Peterson who paraphrased the Message, and several others. The heroes share many of their observations on the North American church, which has been largely influenced by power, prestige, platform and personality.