Directions for improving interaction among local authorities to ensure sustainable regional development in ukraine

<jats:p>The article substantiates directions for improving interaction among local authorities to ensure sustainable regional development in Ukraine amid wartime risks, widening territorial disparities, reform of public investment management, and preparation for post-war recovery. The purpose of the study is to develop the organizational and institutional foundations for coordination among local self-government bodies, regional authorities, and other regional development actors, so that strategic priorities, joint projects, resources, and outcomes align with economic, social, environmental, and spatial sustainability objectives. The methodological framework combines systemic, institutional, and structural-functional approaches; comparison; content analysis of current legislation and recent academic publications; and logical modeling. The study demonstrates that the formal availability of powers and cooperation agreements does not, in itself, produce a regional development effect when interaction remains episodic, project-fragmented, and unsupported by shared data, clear financial responsibility, and joint monitoring. The scientific novelty consists in a five-contour model of local-government coordination that integrates strategic-spatial, intermunicipal, investment-project, digital-information, and partnership-participatory dimensions. In addition, a three-level interaction maturity matrix is proposed to distinguish among fragmented, coordinated, and integrated interactions. The matrix can be used as a diagnostic tool for communities and regions and as a basis for selecting institutional interventions. The practical significance of the results lies in the possibility of applying the model to update regional and local development strategies, design intermunicipal projects, prepare medium-term public investment plans and unified project portfolios within the DREAM ecosystem, and coordinate recovery initiatives with international partners. Particular attention is paid to the need to move from cooperation based on separate agreements to portfolio-based governance, common indicators, interoperable data, shared project offices, and result-oriented financing. Further research should focus on the empirical validation of coordination-capacity indicators, the comparison of different types of Ukrainian regions and communities, and the quantitative assessment of the relationship between the quality of intergovernmental interaction and sustainable development outcomes during recovery and European integration. Keywords: territorial communities, decentralization, mechanism, strategic planning, local budgets, model, digitalization, transparency, interaction, local authorities, investment development of the region, digital technologies, public services, European integration, sustainable development of the region, public investments, DREAM, coordination capacity, territorial communities.</jats:p>