This book presents a radical, empirical investigation of how national courts "react" to disputes involving international organizations, analyzing in particular whether such organizations should be immune to national jurisdictions. Under the headings "domestic legal personality" and "immunity" of international organizations, some of the issues covered have already been treated in international legal scholarship, mostly in the form of short articles or case notes. This study, however, provides a thorough comparative analysis and the largest compilation of relevant decisions on the subject, making it indispensable for practitioners as well as academics in the field.