Institutes of fourteen Dutch and Belgian universities participate in ICO. These universities constitute the inter-university graduate school ICO:
| Eindhoven University of Technology | • Eindhoven School of Education (ESoE) | 
| Erasmus University Rotterdam | • Erasmus School of Social and Behavioural Sciences | 
| Leiden University | • ICLON: Interfacultair Centrum voor Lerarenopleiding, Onderwijsontwikkeling en Nascholing • Department of Education and Child Studies | 
| Maastricht University | • Faculty of Health, Medicine and Life sciences • School of Business and Economics | 
| Open University of the Netherlands | • Faculty of Educational Sciences • Faculty of Management | 
| Radboud University Nijmegen | • Radboud Docenten Academie • Department of Educational Sciences • Institute for Science Education | 
| TU Delft | – Teaching Academy – Science & Engineering Education | 
| Université Catholique de Louvain | • Education and Training School (EDEF) | 
| University of Amsterdam | • Faculty of Social and Behavioural Sciences (FMG): Afdeling Pedagogische en Onderwijswetenschappen | 
| University of Antwerp | • Faculty of Social Sciences | 
| University of Groningen | • Faculty of Behavioural and Social Sciences with Nieuwenhuis Institute for Educational Research | 
| University of Twente | • Faculty of Behavioural, Management and Social Sciences | 
| Utrecht University | • Faculty of Social Sciences • Freudenthal Institute • Utrecht Center for Research and Development of Health Professions Education UMCU • Institute for Language Sciences | 
| Vrije Universiteit Amsterdam | • Faculty of Behavioural and Human Movement Sciences • The Institute for Education and Training, VUmc School of Medical Sciences | 
| Wageningen University | • Departement of Social Sciences with Leerstoelgroep Education and Learning Sciences |