The mentoring program pairs unrelated adult volunteers with youths from single-parent households. The mentor and the youth make a substantial time commitment, meeting for about 4 hours two to four times a month for at least 1 year. Developmentally appropriate activities shared by the mentor and the youth may include taking walks; attending a play, movie, school activity, or sporting event; playing catch; visiting the library; washing the car; or just sharing thoughts. The relationship and activities are designed to enhance communication skills, develop relationship skills, and support positive decisionmaking. Eight mentoring sites throughout the Nation were selected for an evaluation conducted by Public/Private Ventures. Youths in the study were between 10 and 16 years old; slightly more than 50 percent were boys, and more than 50 percent were minority youths; many were from low-income households. Evaluation findings show that mentored youth were 46 percent less likely than controls to initiate drug use during the study period, and mentored youth were 27 percent less likely than controls to initiate alcohol use during the study period. These and other findings provide clear evidence that mentoring programs can create and support caring relationships between adults and youth that result in a wide range of benefits that involve positive behavior and attitudes. This article also discusses program elements essential for success, the effect of matching mentor to youth, program replication obstacles, and applications for social policy and youth programming.