Mentoring programs are increasingly popular as preventive and/or supportive interventions for youth with various needs. A meta-analysis of mentoring program effects conducted by DuBois, Holloway, Valentine, and Cooper (2002) suggests that youth from backgrounds of risk (defined broadly) have the capacity to benefit from mentoring, especially when best practices are employed and strong relationships are formed. Strong mentoring programs for special populations of youth may promote positive youth-mentor relationships and build a sense of trust in others. However, objective measures to assess the outcomes of mentoring relationships with youth are lacking in the literature (Nakkula and Harris, 2005). This paper describes an objective method to assess the outcomes of mentoring relationships with five special populations that are frequent participants in mentoring programs: (1) abused and neglected youth; (2) youth with disabilities; (3) pregnant and parenting adolescents; (4) juvenile offenders; and (5) academically at-risk students. The paper presents the results of a pilot evaluation of Goal Attainment Scaling (GAS) conducted with five mentoring programs serving youth offenders, youth with disabilities, at-risk college students, and underachieving youth. The authors also evaluated the mentors' perceptions of the benefits and/or challenges of using goal attainment scaling and engaging in goal-driven mentoring relationships. (Contains 1 note and 1 table.)