Why a new journal about diplomacy? The answer relates to both the form and the substance of what diplomacy is and does. Diplomatic history has had something of a tarnished reputation since at least the 1970s. A field that set itself the task of recreating the mechanisms of interstate relations by focusing on the archives of foreign ministries was facing something of a credibility crisis. States have continued to shape world order, but not as the only actors. Social history "from below" has rejected and looked beyond the elite-based focus of traditional diplomatic history. Economic history has broadened the context within which diplomatic decisions are taken. The subjectivities of emissaries and representatives of diplomacy have been dissected using race, class, and gender lenses. Post-colonial history has questioned the assumptions of Western norms and "origins" to diplomacy, pointing to other paths that were long written out of that normative history. Transnational history has highlighted the role of social movements and entanglements that undermine the notion of the unitary state. Global history has situated the local event within the wider scope of all-encompassing trends through time. Applied history has situated current events in a comparative setting in search of patterns and lessons. Contemporary history, as illustrated by this issue's Brexit forum, has done the opposite in tracing their origins and evolution in our own era. Diplomatic history, faced with these waves of innovation by fellow historians, was seeing its raison d'être being undermined. Once regarded as an eminent branch of historical study, it has declined, and in some universities, even disappeared. Yet, diplomacy has not disappeared as an essential tool with which to enable world politics to function. The decline of diplomatic history that began some fifty years ago was in part the result of a narrow, and in our view, misguided, view of diplomacy and its history. The array of those involved in these processes has since grown wider, giving space-however grudgingly at timesto non-state actors. Just as another subfield to experience a decline-military history-is not the exclusive account of professional armies on battlefields, diplomatic history now involves much more-to recall the infamous slightthan "what one clerk said to another."