The review concludes that the balance of reliable evidence from the international literature indicates that extended late-night liquor-selling hours lead to increased consumption of alcoholic beverages and related adverse consequences. Well-controlled studies are needed to confirm this conclusion, however. There is a particular need for well-controlled studies that link liquor-selling hours to rates of alcohol use and related harms using controls for concurrent economic and other regulatory changes that use validated measures of alcohol-related consumption and harm. Specifically, well-controlled studies that relate liquor-selling hours to level of violence are needed. Of the 49 studies that met inclusion criteria for the review, only 14 included baseline and control measures as well as peer review. Of these 14 studies, 11 reported at least 1 significant outcome that showed adverse effects from increasing hours for serving liquor for on-premise consumption or benefits from reducing liquor-selling hours. Controlled studies with fewer methodological problems were also most likely to report such effects. 1 table and 68 references