ABSTRACT
Before the Cold War ended, the EU had only twelve members. It enlarged to fifteen in 1995, to twenty-five in 2004, and to twenty-seven in 2007. In spite of the political importance of the process, the scientific community has not yet offered a ‘grand theory’ to explain the large-scale process of institutional expansion – the OSCE, the CoE and NATO admitted new members, too – in Europe in the 1990s (cf. Croft et al. 1999).
