Tjeerd Plomp is
- Professor Emeritus at the University of Twente, Netherlands (retired in 1999) where he was Professor of Education since 1981.
- 1982-1985 Dean of the Faculty of Educational Science and Technology
- 1986-1989 Director of OCTO (Institute for Applied Educational Research)
- 1989- 1999 Chair of the International Association for the Evaluation of Educational Achievement (IEA).
- Chair of the Steering Committee for several IEA studies (TIMSS 1995, SITES-M1, and SITES-M2), and director of the IEA Computers in Education Study and the Second Information Technology in Education Study 2006. Honorary doctor in psychology and pedagogical sciences of the University of Ghent (1996).
- Honorary member of the IEA (since 1999).
- Extraordinary Professor of Education, Faculty of Education, University of Pretoria, South Africa (2003–2005).
- As Chair of the Organizing Committee of the first ECER in 1992, Tjeerd Plomp is one of the founding fathers of the European Conferences on Educational Research and the European Educational Research Association. Tjeerd Plomp has steered Network 9 for over a decade, both as Link Convenor (2006–2008) and Co-convenor (1999–2006 and 2008–2011).