This work studied the efforts of the Technical Committee on Cultural Heritage in Cyprus to explore how effectively the TCCH applies diplomatic relation-building efforts towards cultural heritage management and how this can be used to construct a bridge to a process of sustainable development of social relations and heritage use in Cyprus. The Committee’s efforts demonstrate community heritage diplomacy and civil heritage diplomacy, employed by the two largest communities of the island as they attempt to build relations with each other and other minor communities across the border via various heritage practices, and public heritage diplomacy, which is employed by the authorities of each side via the Committee to influence the public of the other side. The Committee employs these forms of heritage diplomacy via a language of cooperation and by bridging gaps in and crossing borders for collaboration, so as to transfer knowledge, values, and experience, and to build trust with institutions and communities. The significance of the study lies in illustrating that the technical and collaborative successes of the Committee via application of the determined types of diplomacy may be successfully applied for a sustainable approach to build relations and confidence under ideologically and politically strained circumstances in Cyprus.