Alcohol consumption is widely distributed in the population in most parts of the world, with abstainers in a minority among adults in most developing societies but in a majority in many less developed societies. Those qualifying to be diagnosed with an alcohol use disorder are usually a relatively small minority of drinkers. On the other hand, alcohol is causally implicated in a wide variety of health and social problems. The WHO Global Burden of Disease (GBD) study for 2000 estimated that alcohol accounted globally for 4 per cent of the total health-related loss of disability-adjusted life years (DALYs), for 6.8 per cent in developed societies like those in Western Europe and North America, and for 12.1 per cent in Eastern Europe and Central Asia. In terms of where this burden appears in the health system, while psychiatric conditions (including dependence) and chronic physical disease are both important, casualties often play a predominant role. The GBD 2000 study calculated that injuries accounted for 40 per cent of the DALYs lost worldwide due to alcohol. The public health importance of acute effects of a particular episode of intoxication underlies what is often described as the ‘prevention paradox’. In many societies, a fairly substantial proportion of the population (particularly of males) gets intoxicated at least occasionally, and by that fact is at risk of experiencing and causing social and health harm from drinking. Preventing alcohol problems thus requires looking beyond the considerably smaller segment of the population diagnosable with an alcohol use disorder, or the even smaller segment receiving treatment for such a disorder. A complication in preventing alcohol problems is that there is also evidence of a health benefit from drinking in terms of reduced cardiovascular disease. This benefit is, however, important mainly for men over 45 and women past menopause, and can be attained with a pattern of very light regular drinking, as little as a drink every second day. There is thus little potential conflict between taking alcohol as a preventive heart medication and any prevention policy short of total prohibition. Simplifying somewhat, there are seven main strategies to minimize alcohol problems. One strategy is to educate or persuade people not to use or about ways to use so as to limit harm. A second strategy, a kind of negative persuasion, is to deter drinking-related behaviour with the threat of penalties. A third strategy, operating in the positive direction, is to provide alternatives to drinking or to drink-connected activities. A fourth strategy is in one way or another to insulate the use from harm. A fifth strategy is to regulate availability of the drug or the conditions of its use. Prohibition of supply may be regarded as a special case of such regulation. A sixth strategy is to work with social or religious movements oriented to reducing alcohol problems. And a seventh strategy is to treat or otherwise help people who are in trouble with their drinking. We will consider in turn these strategies and the evidence on their effectiveness in reducing rates of alcohol problems in the population.