This volume shows how modern econometric techniques, computational tools, and interdisciplinary approaches are reshaping the analysis of growth, financial markets, and microeconomic behavior in an increasingly complex global economy. Featuring select contributions presented at the 2025 International Conference on Applied Economics (ICOAE) held in Bratislava, Slovakia, this volume applies cutting-edge methodologies such as machine learning, genetic algorithms, wavelet transforms, ARIMA-GARCH modeling, and emerging uses of  quantum computing to examine financial efficiency, cryptocurrency dynamics, sovereign debt restructuring, ESG risk, and corporate performance.  A central theme is sustainability and structural transformation in which links between economic growth, environmental degradation, green finance, circular-economy practices, and pathways to net-zero emissions are explored. The book also analyses how digitization, innovation, and R&D investment influence development across regions such as the EU, MENA Africa, and OECD economies.  Bridging methodological advancement with policy relevance, this volume serves researchers, policymakers, and advanced students seeking rigorous analysis to inform decisions in sustainable development, financial stability, and digital transformation.