For a long time, cultural objects have been on the move. The author of this book had previously observed that greater insight into the state of affairs was desirable regarding immunity from seizure for cultural objects belonging to foreign States and placed on temporary loan abroad for exhibitions. His monograph, published in 2012, concluded that a (relatively) young rule of customary international law exists to the effect that such objects enjoy immunity from seizure, albeit with certain important exceptions. Since then, a considerable number of relevant new developments have emerged. It was therefore considered timely, for this second, revised edition, to examine whether the earlier conclusion remains valid or requires modification in light of these new developments.