This entry introduces the concept of postdigital diplomacy as the evolution of conventional diplomatic practice within a dynamic, digitised ecosystem where the boundaries between the digital and physical have blurred. In the postdigital condition, characterised by constant technological integration and fluidity, diplomacy adapts in both form and method. Postdigital diplomacy encompasses hybrid practices such as cyberdiplomacy, social media diplomacy, Artificial Intelligence (AI) diplomacy, and virtual diplomacy, reflecting the systemic complexity of postdigital international relations.