Insightful collection of essays, much like his other works but revolving - as one might guess - around the concept of "Mobilization." Predates and is much more subtle than later theorists of the subject like Land and the CCRU while also not being mired in soporific post-Marxism.
I made an audiobook of it here in case that interests you: https://www.youtube.com/playlist?list=PLUDTwO6PkcrBkilJoGwFW5QUnDBiRLgkA