A quasi-experimental study will compare primary health care-based prevention and management of alcohol use disorder, operationalized by heavy drinking, in three intervention cities from Colombia, Mexico and Peru with three comparator cities from the same countries. In the implementation cities, primary health care units (PHCUs) will receive training embedded within ongoing supportive municipal action over an 18-month implementation period. In the comparator cities, practice as usual will continue at both municipal and PHCU levels. The primary outcome will be the proportion of consulting adult patients intervened with (screened and advice given to screen positives).

Inclusion Criteria:

• Any fully trained medical practitioner, nurse or practice assistant
• Non-temporary employment contract
• Working in the selected primary health care centre
• Involved in medical and/or preventive care

Exclusion Criteria:

• Not a fully trained medical practitioner, nurse or practice assistant
• Having a temporary employment contract
• Not working in the selected primary health care centre
• Not involved in medical and/or preventive care