The vast majority of international migrants from developing countries are of working age. And yet, their integration in the formal local labor market of their host countries continues to be a challenge. This paper reviews the scope of mentoring programs as a more systematic policy instrument to facilitate the integration of migrants into the labor market. It synthesizes the multidisciplinary academic research on mentoring. The review highlights the diversity of outcomes indicators and the relevance of context in the choice of mentoring program design. Determinants of success include the personal characteristics of the mentee and of the mentor and the efforts to match them but also the efforts made to account for the human, institutional, financial, and political context in the overall design of programs. Despite the significant progress achieved in understanding the determinants of mentoring effectiveness, the survey shows that there are still many sources of uncertainty on the optimal design of mentoring programs. This justifies a research agenda in a field with growing and significant political and social prominence of direct relevance to both developed and developing countries.