Social host liability laws (also known as teen party ordinances, loud or unruly gathering ordinances, or response costs ordinances) target the location in which underage drinking takes place. Social host liability laws hold noncommercial individuals responsible for underage drinking events on property they own, lease, or otherwise control. They differ from laws prohibiting individuals from providing alcoholic beverages to underage persons; social host laws target providing the venue where underage drinking takes place. According to a College Alcohol Study report on access to alcohol, among the most common settings for underage and heavy drinking for college students are house parties, outdoor parties, or fraternity and sorority parties. This paper describes a review of the research evidence on the effect of social host liability in the Institute of Medicine 2004 report "Reducing Underage Drinking: A Collective Responsibility." Lessons learned from social host ordinances implemented by colleges and universities are presented. (Contains 2 resources.)