BACKGROUND:Government monopolies of markets in hazardous but attractive substances and activities have a long history, though prior to the late 19th century often motivated more by revenue needs than by public health and welfare. METHODS:A narrative review considering lessons from alcohol for monopolization of all or part of legal markets in cannabis as a strategy for public health and welfare. RESULTS:A monopoly can constrain levels of use and harm from use through such mechanisms as price, limits on times and places of availability, and effective implementation of restrictions on who can purchase, and less directly by replacing private interests who would promote sales and press for greater availability, and as a potential test-bed for new policies. But such monopolies can also push in the opposite direction, particularly if revenue becomes the prime consideration. Drawing on the alcohol experience in recent decades, the paper discusses issues relevant to cannabis legalization in monopolization of different market levels and segments - production, wholesale, import, retail for off-site and for on-site use - and choices about the structuring and governance of monopolies and their organizational location in government, from the perspective of maximizing public health and welfare interests. CONCLUSION:While the historical record is mixed for government monopolies of attractive but hazardous commodities, experience with alcohol in recent decades shows that for public health and welfare public monopolization is generally a preferable option.