I've found this book absolutely brilliant. I saw it advertised in one of the tabloids I was reading at work (someone else's ;-) ) and thought it looked to have some useful information - what an understatement that turned out to be!
First of all, the book covers very many subjects about keeping yourself safe - whether it be on the street, travelling or even online or protecting yourself in your own home.
As an ex-SAS guy, he has a lot of experience, including in war zones and the like, and he really does know what he's talking about. Very refreshing for me also was the fact that he puts his points across pretty bluntly and with no bull - as an ex-squaddie myself, I prefer that style.
The only reason I would hesitate to make this book compulsory for everyone (if I were in charge), is that it would give too many hints about how you were going to defend yourself to potential burglars, kidnappers or assailants!