In the past decades, and as a result of the internationalisation processes experienced by higher education across the world, English-medium education (EME) has gained momentum in universities where well-established national and/or local languages had traditionally been the means of instruction. While this phenomenon is growing at a fast pace, professional support for the lecturers engaged is very often scarce and unsystematic. Against this backdrop, the EU project known as EQUiiP (Educational Quality at Universities for Inclusive International Programmes) takes as point of departure the support of a specific set of agents -- educational developers (EDs) -- who, although essential in the design and implementation of internationalised programmes, has attracted scarce research attention. Drawing conceptually on the ROAD-MAPPING framework (Dafouz, E., and U. Smit. [2016]. "Towards a Dynamic Conceptual Framework for English-Medium Education in Multilingual University Settings." "Applied Linguistics" 37 (3): 397-415) and with the help of data from a baseline survey gathered by EQUiiP, this paper explores the roles, beliefs and practices of EDs in these concrete internationalised programmes. Our findings reveal great differences in these agents' backgrounds and areas of expertise as well as different perspectives on the roles of language(s), and more particularly English, in the process of internationalising higher education.