Transboundary incidents with the potential to develop into crises transcending geographical, cultural and religious boundaries are becoming increasingly common in today's interconnected world. This development poses new demands on governments to communicate with publics on a transnational level, what is commonly referred to as public diplomacy. Based on an inductive comparative case study, this article suggests a framework for understanding public diplomacy as a crisis communication tool consisting of three core tasks: sense making, networking and messaging. The article ends with a proposal as to how public diplomacy can contribute to crisis mitigation.