I first heard about this book when reading Delivering Happiness as Tony Hsieh give it lots of credit and is, at least to some extent, responsible for Zappos’ success.
As it was not available in audio format until recently I postponed getting it. It is now available for free download at http://www.triballeadership.net/.

Tribal Leadership is about moving from individual performances to a group performance. It is about building a tribal culture that make your organisation stronger.

This concept is really interesting and you will take away lots of ideas and thoughts. I have also started to look at organisations and individual around me and see which stage they are at, and sometime start to wonder if they ever will (can) move up to the next stage.
Unfortunately the audio book is abbreviated but it is still a really good and well worth listening to and I suggest you do it a few times.

Update 1 Feb 2012 Have listen to this again and this time it gave me even more. I am quite convinced that a company’s culture, its tribe, is the competitive edge of the future (and even the present).