Dave Snowden is an prodigious and extraordinary thinker and I guess best known as the developer of the Cynefin framework - a decision making tool. I love his blog and read every post. He has had a profound influence on my thinking.
Next year, I hope to see his long awaited book published but in the mean time if you are looking for a succinct introduction to his work take a look at these takeouts (by Sonja Blignaut) and video from a TedX talk he gave in November 2017.
It's an 18 minute summary of the key aspects of his work and a wonderful resource for anyone looking for a succinct introduction.