Approaches to diplomacy tend to be restrictive because of an exclusively interstate insight. Indeed, historically, the state monopoly over diplomacy has always been challenged by private actors. Today, it is defied both from the inside because of growing public fragmentation (every ministry tends to lead its own foreign policy; subnational authorities develop their diplomatic relations) and from the outside (the business sector and civil society play a growing role on the international scene). This proliferation of actors has transformed diplomatic methods. Beyond the binary division between “old diplomacy” – bilateral, secret and resident – and “new diplomacy” – multilateral, public and itinerant – this article shows that diplomacy has to ...