Well, you've introduced a different set of logic from Ianr's Sue. But I'll run with that, too. If I did a study of shops that took such measures and found that shoplifting had dropped by 25% in three months, I'd be rather pleased. If it found it then returned to the same old level after six months, I'd then be miffed. And if I discovered that shops that install these measures take, on average, 57 years to get a return on investment, I'd really question this whole picture of policemen or cctv or whatever lark and deduce it was a bit of a con. And if I then found out that governments did a study of similar measures in public places and they found it was pretty damn ineffective overall, then at that point I would conclude we've all been taken for a ride. A half a billion pound ride at that. CCTV - it may not reduce crime, but at least you get to watch the highlights of your mugging afterwards...