{Reference Type}: Journal Article {Title}: Cannabis legalization, regulation, & control: a review of key challenges for local, state, and provincial officials. {Author}: Caulkins JP;Kilborn ML; {Journal}: Am J Drug Alcohol Abuse {Volume}: 45 {Issue}: 6 {Year}: 2019 {Factor}: 3.912 {DOI}: 10.1080/00952990.2019.1611840 {Abstract}: Background: A number of countries are legalizing the supply of cannabis or are considering doing so. Beyond top-level design questions (e.g., who gets to supply and how will it be taxed?) lie many equally important and thorny regulatory issues concerning retail sale and use. These issues will often be hammered out at the local and state/provincial level by policy makers who are generalists, not experts in substance misuse, let alone cannabis.Objectives: This review provides a framework for thinking about the role of regulation and delves into three important topics with which these leaders will wrestle: Where and when can cannabis be sold? What can retailers sell? And where can their products be used?Methods: Literature review and drawing parallels with alcohol and tobacco regulation.Results: The common thread across these questions is that the public health interest is both nuanced and in conflict with other stakeholder interests, such as companies' desire to maximize sales and profits and governments' desire for tax revenues.Conclusion: There is a need for data and oversight structures that ensure that public health will not lose out over time.