How about a thread of training/tactics books that you have found valuable? Either for yourself, to increase your knowledge base, or for beginners, to introduce them to concepts and techniques?
I'll start out with a couple books I often suggest. Several of them are not "shooting" books, but more related to mindset. Shooting is the easy part--it's the mental side of things that generally needs more work, I think.
Defensive Handgunning. I think the author is a genius.
Basic to intermediate shooting techniques, combined with many of the mental aspects that a lot of people seem to overlook.
Another reviewOn Killing, Dave Grossman. Classic, no library is complete without it.
On Combat, Dave Grossman. This is a great overview and nicely summarizes about 5 other books I've read. This isn't as in-depth as the books it summarizes, but this book delves deeply enough to get a useful understanding of the topics covered more exhaustively elsewhere.
Deadly Force Encounters. Largely covered in "On Combat", but this is the original.
The Gift of Fear, Gavin deBecker. A nice addition to situational awareness training that emphasizes the power of subconscious.
Blink, Malcolm Gladwell. Interesting read related to situational awareness, particularly how we perceive and judge our environment.
Verbal Judo, George Thompson. Great de-escalation resource.
The Survivor Personality, Al Siebert. Mental thought processes and how they affect our approach to challenges.