This report explores the nature of the relationships that mentors form with children and youth in school-based and in community-based programs and suggests benchmarks that all mentoring programs can use to ensure optimal development of supportive relationships. Among the key differences between school- and community-based models are that the former tend to focus more on a youth’s academic success, require a less intensive commitment from volunteers, be more successful in attracting minority volunteers, and cost less. However, both types of mentoring programs can provide settings in which mentors and youth develop close and supportive relationships.