Hexham is a Fellow of both the Royal Anthropological Institute, and the Royal Historical Society has been a member of various professional organizations including the Society for the Scientific Study of Religion, American Academy of Religion, Association for the Sociology of Religion, South African Institute of Race Relations, South African Society for Mission Studies, and the Berliner Gesellschaft fuer Missionsgeschichte of which he was a founding member with Ulrich van der Heyden. Recently he was elected a Fellow of the Centre for Military and Strategic Studies at the University of Calgary.