Health service prevention of alcohol problems is based on screening and primarily involves motivational counselling. Screening may take the form of routine enquiries about drinking habits. Motivational counselling consists in two parts, assessment of readiness to change, and counselling adapted to the readiness to change. Alcohol problems do not generally require intervention by a specialist, but rather by an observer who suggests a change. Doctors and health care authorities alike should pursue the prevention of alcohol problems by such methods as a matter of policy, as this is a demonstrably effective approach which would enable both the need and costs of health care to be reduced.