Research on the quality of mentoring relationships and on the efficacy of mentoring programmes helps to understand principles that mediate children's and youths' positive development and well-being. Of course, evaluations of the efficacy of mentoring programmes are needed to secure powerful strategies of using mentoring services in social and educational systems.
Until now most of the research on mentoring programmes efficiency was conducted following the principles of qualitative methodological approaches. The results of these studies bring the assurance on the importance and benefits of mentoring programmes for prevention or even for intervention on various kinds of developmental issues of vulnerable children or youths.
At the same time, there is a growing interest in research on exploring mechanisms bringing or mediating benefits of mentoring programmes for various kinds of target groups. We argue that the qualitative and interpretative methodological approaches are especially suitable for this kind of research.
Besides, to demonstrate the evolution of the methodology preferred in research on mentoring we present the case of the research studies conducted in the Big Brothers Big Sisters/Pet P youth mentoring programme between 2003 and 2017 in the Czech Republic.