Open Government (OG) as a concept for modernising the public sector is becoming increasingly prominent in recent debates in administrative science. It refers to a model of government and administrative action which, guided by the three premises of transparency, participation and collaboration, shapes the development and implementation of public policies in close interaction with actors from civil society, business and science. OG thus is not necessarily something completely new, but rather follows the tradition of various reform discourses in administrative science: On the one hand, it shows references to concepts of state theory that postulate a development from the democratic state of the 1950s, the active state of the 1960s, the lean state of the 1970s and 1980s, the activating state of the 1990s towards the digital state of the 2000s. On the other hand, with regard to normative models of public administration, in contrast to autonomous and hierarchical administration, it can be classified between the idea of a cooperative and a responsive administration (cf. [1], pp. 253). At the municipal level, the concept is connectable to concepts that see an evolutionary development from the regulatory municipality of the 1950s and 1960s, the social security municipality of the 1970s, the service municipality of the 1990s to the civic municipality of the 2000s [2]. Finally, it is relatively easy to also establish references to the more recent debates on the topos of regional governance [3], [40].
 It is therefore all the more surprising that in the literature on administrative sciences; concepts of OG have so far hardly been applied to the policy field of cross-border cooperation in Europe. In the last 30 years, the action model of territorial cooperation has steadily gained in importance within the overall approach of European policies, both in qualitative terms (contribution to horizontal integration) and in quantitative terms (financial and human resources employed). In addition to numerous INTERREG funding programme areas, a large number of cross-border action structures with varying degrees of institutionalisation have developed over time at different interlinked territorial levels (inter-local, inter-regional, macro-regional) [4]. A more recent study [5] comes to the conclusion that Europe's cross-border cooperation today has a personnel capacity of over 21,000 full-time equivalents.
 Using the territorial example of the trinational border regions of the Upper Rhine, the paper examines the extent to which the premises of OG are suitable for the future-oriented development of existing approaches to cross-border cooperation in a post-COVID-19 perspective. On the basis of three case studies it will be worked out which possibilities, challenges and perspectives can concretely arise in order to use the negative experiences gained in the COVID-19 pandemic for a structural and functional repositioning of cross-border cooperation in Europe. Finally, an approach concept will be developed, which shows how public actors of cross-border cooperation can contribute to the realisation of a new truly transnational and development-oriented governance mode through methods and approaches of Open Government.