Canada

As a smoker, this will do absolutely nothing. Just increase tax more so it's too expensive to start. Teens aren't prepared to start a $30 to $90 a week habit and it'll push people like me to cutting back/quitting faster; use that tax to better fund quitting programs and other health efforts. It's already getting expensive to be a smoker with packs nearing $20, if I didn't have the salary I do I would've quit a while ago.

Nicotine is a hell of a drug. Any young people reading this please don't start, and if you have stop while you can. A routine is a powerful thing to break from.

Edit: what New Zealand is doing by restricting people after a certain birth year from buying all together I think it's one of the better ways of doing it. If buying cigarettes will always be that much of a hassle it won't be worth starting. That along with increased taxes I think would be the best way forward to stamp out cigarettes in my lifetime.