As the below recommendation features footage of real violence, I believe this warrants a content warning. I haven't seen this posted here before. At some point (I think in the last few years) "Active Self Protection" has exploded into a whole business, with a website shop, Facebook page, the works. I wanted to share the YouTube channel because the Facebook group can get exceptionally political, and as many folks here are in the UK and elsewhere with stricter gun laws, those types of discussions might be less than pertinent. But I like the YouTube channel, which features numerous videos of security cam footage capturing a variety of real acts of violence and how the victims protected themselves (or failed.) They are always accompanied with commentary that tries to distill some self-defense lessons from what was viewed. I hope someone finds these videos worthwhile.