Has anyone read or know of good chess books on defensive techniques? Books that teach good defensive ideas that are frequently used, like pawn shelters, pawn pushing to block pawns etc?

Secrets of Chess Defence by Mihail Marin got a pretty positive review from John Watson, once Watson got over a few personal quirks of Marin.

It seems that the book does categorise the different defensive ideas, a few of them you mentioned, which is supposed to make it easier for the reading, and improving player to absord the ideas.

I haven't ever read the book though, I just happened to see the cover once when in a library, and googled a review afterwards, but there you go, a suggestion atleast.

Thanks, sounds intresting. I'll have a looksie.