A fantastic book.
Top read.
He is very upfront about some of the changes in the later edition (M&R) and clearly explains his changes of view, as all good practitioners should in my opinion.
One grows and learns.
I can't recommend it highly enough for anyone seeking to address communication and behaviour challenges head on, as opposed to merely tolerating, and possibly encouraging them.
I liked it so much I emailed him to tell him so and got a very nice reply.