Jan Hallebeek will become emeritus in April 2019. That will mark an end to his professional career as Researcher and Lecturer on a Royal Netherlands Academy of Arts and Sciences post (1989–1999), as Professor Extraordinarius at the Theological Faculty of the University of Utrecht (1997–2006), and as Professor on the Chair of Legal History at the Vrije Universiteit Amsterdam (from 1999 onwards).
These positions reflect two focal points of his research: on the one hand Church history and Canon Law, on the other hand classical and particularly medieval Roman law and their history. They matched very felicitously his engagement for and in the Old-Catholic Church. The contributions centre on the themes and questions the honorand has pursued in his work till now.