The Interuniversity Graduate School of Psychometrics and Sociometrics (IOPS) was officially founded on June 24th, 1987 as an institute for the advanced dissertation training in psychometrics and sociometrics; it also coordinates the high-quality research in this area. The institute received a starting subsidy of the Ministry of Education for a period of five years.

In 1994, IOPS was officially recognized by the KNAW (Royal Netherlands Academy of Arts and Sciences) as a Graduate School (‘onderzoekschool’), and this recognition was prolonged in June1999, and in June 2004.

In this graduate school participate: University of Amsterdam, Twente University, University of Groningen, Leiden University, Utrecht University, Tilburg University, and Catholic University of Louvain (KULeuven).