This paper analyzes the extent of parliamentary control over European Union (EU) affairs, exercised by the ten Central and Eastern European EU member states. It asks the following three research questions: 1) Do CEE control systems reveal a mutual homogeneity?; 2) Are the formal rules of these control systems stable over time?; and 3) Is there a considerable difference between the capacity and operation of the control systems under analysis? The paper presents the following main findings: 1) the CEE control systems reveal a large degree of heterogeneity, varying from the ‘mixed’ to ‘mandating’ and ‘document-based’, and even the ‘informal’ model; 2) their formal set-up shows, except in the case of Romania, a relative stability; 3) in particular, the Hungarian case shows that there can be a considerable difference between the capacity and operations of the control systems which were analyzed.