As the youth mentoring field has expanded since MENTOR's founding in 1990, so have the questions about the scope of mentoring relationships, who is finding the mentoring they need, and who is being left behind. MENTOR began its efforts to answer these questions almost a decade ago with the publication of "The Mentoring Effect (ED558065)," a study that revealed not only the benefits of mentors of all types, but also the inequities in who gets mentoring -- this is where the authors first defined the "mentoring gap" of one in three young people growing up without a mentor. "Who Mentored You?," a new research study by MENTOR, revisits this mentoring gap to see if the mentoring movement has succeeded in closing it, offering a fresh multigenerational look at the mentoring experiences of all Americans. [Funding for this report was provided by EY. For the full report, see ED626846.]