Randomized Controlled Trial of Big Brothers Big Sisters Mentoring for Prevention of Crime and Delinquency

Inclusion criteria: * youth is 10 years of age or older * youth is likely to be eligible for the Big Brothers Big Sisters Community-Based Mentoring program as determined by initial assessment of program staff Exclusion criteria: * youth has a severe learning, cognitive or other intellectual disability as reported by the parent * parent does not both speak and read either English or Spanish * youth does not have a sibling who is already a study participant * youth has been matched with a Big Brother/Sister through one of the affiliate's programs in the past * youth has a sibling currently receiving services from the affiliate for whom services were initiated (i.e., inquiry was made) prior to start of the study * youth belongs to a group that the affiliate is excluding from study participation based on previous agreement with the research team * youth is designated as an exception case by affiliate staff (each affiliate will have the opportunity to exclude up to 4% of study-eligible youth from the research prior to consent and random assignment for any reason deemed appropriate (e.g., perceived high need of the youth))