Review of benefits and challenges of co‐supervision in doctoral education

Co‐supervision is a widespread practice in doctoral education; however, little is known about its effective implementation. Co‐supervision is defined here as a form of collaborative supervision where two supervisors guide and support one supervisee's research work in a doctoral study. Four drivers that have contributed to the widespread practice of co‐supervision are identified. We refer to these four drivers as the four Is. The four Is represent emerging policy and institutional strategies focusing on (1) interdisciplinarity, (2) intersectoral collaboration, (3) internationalisation as well as (4) efforts to improve the quality of supervision. This review of research evidence focused on understanding the four Is as drivers of co‐supervision in doctoral education; specifically, by analysing benefits and challenges of co‐supervision. A systematic literature review was conducted using the PRISMA‐P protocol for peer‐reviewed articles between 2005 and 2020. Findings show that the drivers linked to improving the quality of supervision and interdisciplinarity usually coincide, while internationalisation was the least frequently mentioned driver. Although no clear patterns emerge between the four drivers identified and benefits and challenges, we observe that challenges related to co‐supervision are mainly addressed in articles that highlight efforts to improve doctoral education and in articles that addressed interdisciplinary drivers behind co‐supervision.