We sought to understand why three countries with similar political systems and similar anti-smoking policy histories developed such very different policies towards e-cigarettes. All appealed to a value-free concept of “evidence” in making use of precautionary and harm reduc-tion principles to deal with the remaining uncertainties in the evidence. Yet policy processes were mediated by important contextual factors. These included: the nature and role of the state in each country; the polit-ical parties in power at the time e-cigarettes were first introduced; the role played by existing regulatory institutions in dealing with e-cigarettes; longer-term changes in ways of thinking about tobacco smoking within public health; the specific pre-history of tobacco control policy, nico-tine and smoking cessation services; the organisation of professional and activist networks that were in favour of and against e-cigarettes; the uses of fear to discourage e-cigarette use; and the influence (or lack thereof) of harm reduction ideas from drug or AIDS policy on tobacco control policy. The object of policy also differed between countries from protecting the smoker to protecting children and young people.

We sought to understand why three countries with similar political systems and similar anti-smoking policy histories developed such very different policies towards e-cigarettes. All appealed to a value-free concept of “evidence” in making use of precautionary and harm reduc-tion principles to deal with the remaining uncertainties in the evidence. Yet policy processes were mediated by important contextual factors. These included: the nature and role of the state in each country; the polit-ical parties in power at the time e-cigarettes were first introduced; the role played by existing regulatory institutions in dealing with e-cigarettes; longer-term changes in ways of thinking about tobacco smoking within public health; the specific pre-history of tobacco control policy, nico-tine and smoking cessation services; the organisation of professional and activist networks that were in favour of and against e-cigarettes; the uses of fear to discourage e-cigarette use; and the influence (or lack thereof) of harm reduction ideas from drug or AIDS policy on tobacco control policy. The object of policy also differed between countries from protecting the smoker to protecting children and young people.