This StateScan publication is the 8th in a series that distills knowledge from NCJJ’s Juvenile Justice Geography, Policy, Practice & Statistics website. The publication summarizes the results of an analysis of 2014 juvenile statutes for U.S. age boundaries of delinquency, and compares upper, lower, and extended ages of original juvenile court jurisdiction for all 50 United States, the District of Columbia, and U.S. territories (American Samoa, Guam, Northern Mariana Islands, Puerto Rico, and the Virgin Islands). The author provides a brief overview of how age boundaries for delinquency create the foundation for juvenile justice, controversy, and trends among the states, and the larger schema of youth crime and other violations subject to the jurisdiction of other courts.